Every problem in the chapter beside the book’s answer, a chapter at a time as you scroll.

Chapter 2: Solving Linear Equations

501 problems · 170 figures

Be Prepared 2.1 §2.1 source ↗

Simplify: 32(12x+20).
If you missed this problem, review Example 1.51.
Example 1.51 in the book ↗

Answer

18 x + 30

Be Prepared 2.2 §2.1 source ↗

Simplify: 5−2(n+1).
If you missed this problem, review Example 1.55.
Example 1.55 in the book ↗

Answer

3 − 2 n

Be Prepared 2.3 §2.1 source ↗

Find the LCD of 56 and 14.
If you missed this problem, review Example 1.28.
Example 1.28 in the book ↗

Answer

12

Try It 2.1 §2.1 source ↗

Determine whether the values are solutions to the equation: 9y+2=6y+3.

ⓐ y=43 ⓑ y=13

Answer

ⓐ no ⓑ yes

Try It 2.2 §2.1 source ↗

Determine whether the values are solutions to the equation: 4x−2=2x+1.

ⓐ x=32 ⓑ x=−12

Answer

ⓐ yes ⓑ no

Try It 2.3 §2.1 source ↗

Solve: 2(m−4)+ 3= −1.

Answer

m = 2

Try It 2.4 §2.1 source ↗

Solve: 5(a−3)+ 5= −10.

Answer

a = 0

Try It 2.5 §2.1 source ↗

Solve: 13(6u+3)= 7− u.

Answer

u = 2

Try It 2.6 §2.1 source ↗

Solve: 23(9x−12)= 8+ 2x.

Answer

x = 4

Try It 2.7 §2.1 source ↗

Solve: 6(p−3)− 7= 5(4p+3)− 12.

Answer

p = −2

Try It 2.8 §2.1 source ↗

Solve: 8(q+1)− 5= 3(2q−4)− 1.

Answer

q = −8

Try It 2.9 §2.1 source ↗

Solve: 6[4−2(7y−1)]= 8(13−8y).

Answer

y = − 17 5

Try It 2.10 §2.1 source ↗

Solve: 12[1−5(4z−1)]= 3(24+11z).

Answer

z = 0

Try It 2.11 §2.1 source ↗

Classify the equation as a conditional equation, an identity, or a contradiction and then state the solution: 4+ 9(3x−7)= −42x− 13+ 23(3x−2).

Answer

identity; all real numbers

Try It 2.12 §2.1 source ↗

Classify the equation as a conditional equation, an identity, or a contradiction and then state the solution: 8(1−3x)+ 15(2x+7)= 2(x+50)+ 4(x+3)+ 1.

Answer

identity; all real numbers

Try It 2.13 §2.1 source ↗

Classify the equation as a conditional equation, an identity, or a contradiction and then state the solution: 11(q+3)− 5= 19.

Answer

conditional equation; q=−911

Try It 2.14 §2.1 source ↗

Classify the equation as a conditional equation, an identity, or a contradiction and then state the solution: 6+14(k−8)= 95.

Answer

conditional equation; k=20114

Try It 2.15 §2.1 source ↗

Classify the equation as a conditional equation, an identity, or a contradiction and then state the solution: 12c+ 5(5+3c)= 3(9c−4).

Answer

contradiction; no solution

Try It 2.16 §2.1 source ↗

Classify the equation as a conditional equation, an identity, or a contradiction and then state the solution: 4(7d+18)= 13(3d−2)− 11d.

Answer

contradiction; no solution

Try It 2.17 §2.1 source ↗

Solve: 14x+12=58.

Answer

x = 1 2

Try It 2.18 §2.1 source ↗

Solve: 18x+12=14.

Answer

x = −2

Try It 2.19 §2.1 source ↗

Solve: 7= 12x+ 34x− 23x.

Answer

x = 12

Try It 2.20 §2.1 source ↗

Solve: −1= 12u+ 14u− 23u.

Answer

u = −12

Try It 2.21 §2.1 source ↗

Solve: 15(n+3)= 14(n+2).

Answer

n = 2

Try It 2.22 §2.1 source ↗

Solve: 12(m−3)= 14(m−7).

Answer

m = −1

Try It 2.23 §2.1 source ↗

Solve: 3r+56+ 1= 4r+33.

Answer

r = 1

Try It 2.24 §2.1 source ↗

Solve: 2s+32+ 1= 3s+24.

Answer

s = −8

Try It 2.25 §2.1 source ↗

Solve: 0.25n+ 0.05(n+5)= 2.95.

Answer

n = 9

Try It 2.26 §2.1 source ↗

Solve: 0.10d+ 0.05(d−5)= 2.15.

Answer

d = 16

2.1-1 §2.1 source ↗

Solve Equations Using the General Strategy

In the following exercises, determine whether the given values are solutions to the equation.

6 y + 10 = 12 y

ⓐ y=53 ⓑ y=−12

Answer

ⓐ yes ⓑ no

2.1-3 §2.1 source ↗

Solve Equations Using the General Strategy

In the following exercises, determine whether the given values are solutions to the equation.

8 u − 1 = 6 u

ⓐ u=−12 ⓑ u=12

Answer

ⓐ no ⓑ yes

2.1-5 §2.1 source ↗

In the following exercises, solve each linear equation.

15 ( y − 9 ) = −60

Answer

y = 5

2.1-7 §2.1 source ↗

In the following exercises, solve each linear equation.

− ( w − 12 ) = 30

Answer

w = −18

2.1-9 §2.1 source ↗

In the following exercises, solve each linear equation.

51+ 5(4−q)= 56

Answer

q = 3

2.1-11 §2.1 source ↗

In the following exercises, solve each linear equation.

3(10−2x)+ 54= 0

Answer

x = 14

2.1-13 §2.1 source ↗

In the following exercises, solve each linear equation.

2 3 ( 9 c − 3 ) = 22

Answer

c = 4

2.1-15 §2.1 source ↗

In the following exercises, solve each linear equation.

1 5 (15c+10)= c+ 7

Answer

c = 5 2

2.1-17 §2.1 source ↗

In the following exercises, solve each linear equation.

3(4n−1)− 2= 8n+ 3

Answer

n = 2

2.1-19 §2.1 source ↗

In the following exercises, solve each linear equation.

12+ 2(5−3y)= −9(y−1)− 2

Answer

y = −5

2.1-21 §2.1 source ↗

In the following exercises, solve each linear equation.

5+ 6(3s−5)= −3+ 2(8s−1)

Answer

s = 10

2.1-23 §2.1 source ↗

In the following exercises, solve each linear equation.

4(p−4)− (p+7)= 5(p−3)

Answer

p = −4

2.1-25 §2.1 source ↗

In the following exercises, solve each linear equation.

4[5−8(4c−3)]= 12(1−13c)− 8

Answer

c = −4

2.1-27 §2.1 source ↗

In the following exercises, solve each linear equation.

3[−9+8(4h−3)]= 2(5−12h)− 19

Answer

h = 3 4

2.1-29 §2.1 source ↗

In the following exercises, solve each linear equation.

5[2(m+4)+8(m−7)]= 2[3(5+m)−(21−3m)]

Answer

m = 6

2.1-31 §2.1 source ↗

Classify Equations

In the following exercises, classify each equation as a conditional equation, an identity, or a contradiction and then state the solution.

23z+ 19= 3(5z−9)+ 8z+ 46

Answer

identity; all real numbers

2.1-33 §2.1 source ↗

Classify Equations

In the following exercises, classify each equation as a conditional equation, an identity, or a contradiction and then state the solution.

18(5j−1)+ 29= 47

Answer

conditional equation;j=25

2.1-35 §2.1 source ↗

Classify Equations

In the following exercises, classify each equation as a conditional equation, an identity, or a contradiction and then state the solution.

22(3m−4)= 8(2m+9)

Answer

conditional equation; m=165

2.1-37 §2.1 source ↗

Classify Equations

In the following exercises, classify each equation as a conditional equation, an identity, or a contradiction and then state the solution.

7v+ 42= 11(3v+8)− 2(13v−1)

Answer

contradiction; no solution

2.1-39 §2.1 source ↗

Classify Equations

In the following exercises, classify each equation as a conditional equation, an identity, or a contradiction and then state the solution.

45(3y−2)= 9(15y−6)

Answer

contradiction; no solution

2.1-41 §2.1 source ↗

Classify Equations

In the following exercises, classify each equation as a conditional equation, an identity, or a contradiction and then state the solution.

9(14d+9)+ 4d= 13(10d+6)+ 3

Answer

identity; all real numbers

2.1-43 §2.1 source ↗

Solve Equations with Fraction or Decimal Coefficients

In the following exercises, solve each equation with fraction coefficients.

1 4 x − 1 2 = − 3 4

Answer

x = −1

2.1-45 §2.1 source ↗

Solve Equations with Fraction or Decimal Coefficients

In the following exercises, solve each equation with fraction coefficients.

5 6 y − 2 3 = − 3 2

Answer

y = −1

2.1-47 §2.1 source ↗

Solve Equations with Fraction or Decimal Coefficients

In the following exercises, solve each equation with fraction coefficients.

1 2 a + 3 8 = 3 4

Answer

a = 3 4

2.1-49 §2.1 source ↗

Solve Equations with Fraction or Decimal Coefficients

In the following exercises, solve each equation with fraction coefficients.

2= 1 3 x− 1 2 x+ 2 3 x

Answer

x = 4

2.1-51 §2.1 source ↗

Solve Equations with Fraction or Decimal Coefficients

In the following exercises, solve each equation with fraction coefficients.

1 3 w + 5 4 = w − 1 4

Answer

w = 9 4

2.1-53 §2.1 source ↗

Solve Equations with Fraction or Decimal Coefficients

In the following exercises, solve each equation with fraction coefficients.

1 3 b+ 1 5 = 2 5 b− 3 5

Answer

b = 12

2.1-55 §2.1 source ↗

Solve Equations with Fraction or Decimal Coefficients

In the following exercises, solve each equation with fraction coefficients.

1 4 (p−7)= 1 3 (p+5)

Answer

p = −41

2.1-57 §2.1 source ↗

Solve Equations with Fraction or Decimal Coefficients

In the following exercises, solve each equation with fraction coefficients.

1 2 ( x + 4 ) = 3 4

Answer

x = − 5 2

2.1-59 §2.1 source ↗

Solve Equations with Fraction or Decimal Coefficients

In the following exercises, solve each equation with fraction coefficients.

4 n + 8 4 = n 3

Answer

n = −3

2.1-61 §2.1 source ↗

Solve Equations with Fraction or Decimal Coefficients

In the following exercises, solve each equation with fraction coefficients.

3 x + 4 2 + 1= 5 x + 10 8

Answer

x = −2

2.1-63 §2.1 source ↗

Solve Equations with Fraction or Decimal Coefficients

In the following exercises, solve each equation with fraction coefficients.

7 u − 1 4 − 1= 4 u + 8 5

Answer

u = 3

2.1-65 §2.1 source ↗

In the following exercises, solve each equation with decimal coefficients.

0.4x+ 0.6= 0.5x− 1.2

Answer

x = 18

2.1-67 §2.1 source ↗

In the following exercises, solve each equation with decimal coefficients.

0.9x− 1.25= 0.75x+ 1.75

Answer

x = 20

2.1-69 §2.1 source ↗

In the following exercises, solve each equation with decimal coefficients.

0.05n+ 0.10(n+8)= 2.15

Answer

n = 9

2.1-71 §2.1 source ↗

In the following exercises, solve each equation with decimal coefficients.

0.10d+ 0.25(d+5)= 4.05

Answer

d = 8

2.1-73 §2.1 source ↗

In the following exercises, solve each equation with decimal coefficients.

Fencing Micah has 74 feet of fencing to make a dog run in his yard. He wants the length to be 2.5 feet more than the width. Find the length, L, by solving the equation 2L+ 2(L−2.5)= 74.

Answer

L=19.75 feet

2.1-75 §2.1 source ↗

In the following exercises, solve each equation with decimal coefficients.

Using your own words, list the steps in the general strategy for solving linear equations.

Answer

Answers will vary.

2.1-77 §2.1 source ↗

In the following exercises, solve each equation with decimal coefficients.

What is the first step you take when solving the equation 3− 7(y−4)= 38? Why is this your first step?

Answer

Answers will vary.

2.1-79 §2.1 source ↗

In the following exercises, solve each equation with decimal coefficients.

If an equation has fractions only on one side, why do you have to multiply both sides of the equation by the LCD?

Answer

Answers will vary.

Be Prepared 2.4 §2.2 source ↗

Translate “six less than twice x” into an algebraic expression.
If you missed this problem, review Example 1.8.
Example 1.8 in the book ↗

Answer

2 x − 6

Be Prepared 2.5 §2.2 source ↗

Convert 4.5% to a decimal.
If you missed this problem, review Example 1.40.
Example 1.40 in the book ↗

Answer

0.045

Be Prepared 2.6 §2.2 source ↗

Convert 0.6 to a percent.
If you missed this problem, review Example 1.40.
Example 1.40 in the book ↗

Answer

60 %

Try It 2.27 §2.2 source ↗

Guillermo bought textbooks and notebooks at the bookstore. The number of textbooks was three more than twice the number of notebooks. He bought seven textbooks. How many notebooks did he buy?

Answer

He bought two notebooks.

Try It 2.28 §2.2 source ↗

Gerry worked Sudoku puzzles and crossword puzzles this week. The number of Sudoku puzzles he completed is eight more than twice the number of crossword puzzles. He completed 22 Sudoku puzzles. How many crossword puzzles did he do?

Answer

He did seven crosswords puzzles.

Try It 2.29 §2.2 source ↗

The sum of four times a number and two is fourteen. Find the number.

Answer

3

Try It 2.30 §2.2 source ↗

The sum of three times a number and seven is twenty-five. Find the number.

Answer

6

Try It 2.31 §2.2 source ↗

The sum of two numbers is negative twenty-three. One number is seven less than the other. Find the numbers.

Answer

−15 , −8

Try It 2.32 §2.2 source ↗

The sum of two numbers is negative eighteen. One number is forty more than the other. Find the numbers.

Answer

−29 , 11

Try It 2.33 §2.2 source ↗

Find three consecutive integers whose sum is −96.

Answer

−33 , −32 , −31

Try It 2.34 §2.2 source ↗

Find three consecutive integers whose sum is −36.

Answer

−13 , −12 , −11

Try It 2.35 §2.2 source ↗

Find three consecutive even integers whose sum is 102.

Answer

32, 34, 36

Try It 2.36 §2.2 source ↗

Find three consecutive even integers whose sum is −24.

Answer

−10 , −8 , −6

Try It 2.37 §2.2 source ↗

According to the National Automobile Dealers Association, the average cost of a car in 2014 was $28,400. This was $1,600 less than six times the cost in 1975. What was the average cost of a car in 1975?

Answer

The average cost was $5,000.

Try It 2.38 §2.2 source ↗

US Census data shows that the median price of new home in the U.S. in November 2014 was $280,900. This was $10,700 more than 14 times the price in November 1964. What was the median price of a new home in November 1964?

Answer

The median price was $19,300.

Try It 2.39 §2.2 source ↗

Translate and solve: ⓐ What number is 45% of 80? ⓑ 7.5% of what amount is $1.95? ⓒ 110 is what percent of 88?

Answer

ⓐ 36 ⓑ $26 ⓒ 125%

Try It 2.40 §2.2 source ↗

Translate and solve: ⓐ What number is 55% of 60? ⓑ 8.5% of what amount is $3.06? ⓒ 126 is what percent of 72?

Answer

ⓐ 33 ⓑ $36 ⓒ 175%

Try It 2.41 §2.2 source ↗

One serving of wheat square cereal has 7 grams of fiber, which is 28% of the recommended daily amount. What is the total recommended daily amount of fiber?

Answer

25 grams

Try It 2.42 §2.2 source ↗

One serving of rice cereal has 190 mg of sodium, which is 8% of the recommended daily amount. What is the total recommended daily amount of sodium?

Answer

2,375 mg

Try It 2.43 §2.2 source ↗

Mitzi received some gourmet brownies as a gift. The wrapper said each brownie was 480 calories, and had 240 calories of fat. What percent of the total calories in each brownie comes from fat? Round the answer to the nearest whole percent.

Answer

50%

Try It 2.44 §2.2 source ↗

The mix Ricardo plans to use to make brownies says that each brownie will be 190 calories, and 76 calories are from fat. What percent of the total calories are from fat? Round the answer to the nearest whole percent.

Answer

40%

Try It 2.45 §2.2 source ↗

Find the percent change. (Round to the nearest tenth of a percent.) In 2011, the IRS increased the deductible mileage cost to 55.5 cents from 51 cents.

Answer

8.8 %

Try It 2.46 §2.2 source ↗

Find the percent change. (Round to the nearest tenth of a percent.) In 1995, the standard bus fare in Chicago was $1.50. In 2008, the standard bus fare was 2.25.

Answer

50%

Try It 2.47 §2.2 source ↗

Find ⓐ the amount of mark-up and ⓑ the list price: Jim’s music store bought a guitar at original cost $1,200. Jim marked the price up 50%.

Answer

ⓐ $600 ⓑ $1,800

Try It 2.48 §2.2 source ↗

Find ⓐ the amount of mark-up and ⓑ the list price: The Auto Resale Store bought Pablo’s Toyota for $8,500. They marked the price up 35%.

Answer

ⓐ $2,975 ⓑ $11,475

Try It 2.49 §2.2 source ↗

Nathaly deposited $12,500 in her bank account where it will earn 4% simple interest. How much interest will Nathaly earn in five years?

Answer

He will earn $2,500.

Try It 2.50 §2.2 source ↗

Susana invested a principal of $36,000 in her bank account that earned simple interest at an interest rate of 6.5%. How much interest did she earn in three years?

Answer

She earned $7,020.

Try It 2.51 §2.2 source ↗

Jim lent his sister $5,000 to help her buy a house. In three years, she paid him the $5,000, plus $900 interest. What was the rate of simple interest?

Answer

The rate of simple interest was 6%.

Try It 2.52 §2.2 source ↗

Loren lent his brother $3,000 to help him buy a car. In four years, his brother paid him back the $3,000 plus $660 in interest. What was the rate of simple interest?

Answer

The rate of simple interest was 5.5%.

Try It 2.53 §2.2 source ↗

Eduardo noticed that his new car loan papers stated that with a 7.5% simple interest rate, he would pay $6,596.25 in interest over five years. How much did he borrow to pay for his car?

Answer

He paid $17,590.

Try It 2.54 §2.2 source ↗

In five years, Gloria’s bank account earned $2,400 interest at 5% simple interest. How much had she deposited in the account?

Answer

She deposited $9,600.

2.2-81 §2.2 source ↗

Use a Problem Solving Strategy for Word Problems

List five positive thoughts you can say to yourself that will help you approach word problems with a positive attitude. You may want to copy them on a sheet of paper and put it in the front of your notebook, where you can read them often.

Answer

Answers will vary.

2.2-83 §2.2 source ↗

In the following exercises, solve using the problem solving strategy for word problems. Remember to write a complete sentence to answer each question.

There are 16 girls in a school club. The number of girls is four more than twice the number of boys. Find the number of boys.

Answer

six boys

2.2-85 §2.2 source ↗

In the following exercises, solve using the problem solving strategy for word problems. Remember to write a complete sentence to answer each question.

Huong is organizing paperback and hardback books for her club’s used book sale. The number of paperbacks is 12 less than three times the number of hardbacks. Huong had 162 paperbacks. How many hardback books were there?

Answer

58 hardback books

2.2-87 §2.2 source ↗

Solve Number Word Problems

In the following exercises, solve each number word problem.

The difference of a number and 12 is three. Find the number.

Answer

15

2.2-89 §2.2 source ↗

Solve Number Word Problems

In the following exercises, solve each number word problem.

The sum of three times a number and eight is 23. Find the number.

Answer

5

2.2-91 §2.2 source ↗

Solve Number Word Problems

In the following exercises, solve each number word problem.

The difference of twice a number and seven is 17. Find the number.

Answer

12

2.2-93 §2.2 source ↗

Solve Number Word Problems

In the following exercises, solve each number word problem.

Three times the sum of a number and nine is 12. Find the number.

Answer

−5

2.2-95 §2.2 source ↗

Solve Number Word Problems

In the following exercises, solve each number word problem.

One number is six more than the other. Their sum is 42. Find the numbers.

Answer

18, 24

2.2-97 §2.2 source ↗

Solve Number Word Problems

In the following exercises, solve each number word problem.

The sum of two numbers is 20. One number is four less than the other. Find the numbers.

Answer

8, 12

2.2-99 §2.2 source ↗

Solve Number Word Problems

In the following exercises, solve each number word problem.

One number is 14 less than another. If their sum is increased by seven, the result is 85. Find the numbers.

Answer

32, 46

2.2-101 §2.2 source ↗

Solve Number Word Problems

In the following exercises, solve each number word problem.

The sum of two numbers is 14. One number is two less than three times the other. Find the numbers.

Answer

4, 10

2.2-103 §2.2 source ↗

Solve Number Word Problems

In the following exercises, solve each number word problem.

The sum of two consecutive integers is 77. Find the integers.

Answer

38, 39

2.2-105 §2.2 source ↗

Solve Number Word Problems

In the following exercises, solve each number word problem.

The sum of three consecutive integers is 78. Find the integers.

Answer

25, 26, 27

2.2-107 §2.2 source ↗

Solve Number Word Problems

In the following exercises, solve each number word problem.

Find three consecutive integers whose sum is −36.

Answer

−11 , −12 , −13

2.2-109 §2.2 source ↗

Solve Number Word Problems

In the following exercises, solve each number word problem.

Find three consecutive even integers whose sum is 258.

Answer

84, 86, 88

2.2-111 §2.2 source ↗

Solve Number Word Problems

In the following exercises, solve each number word problem.

Find three consecutive odd integers whose sum is −213.

Answer

−69 , −71 , −73

2.2-113 §2.2 source ↗

Solve Number Word Problems

In the following exercises, solve each number word problem.

Philip pays $1,620 in rent every month. This amount is $120 more than twice what his brother Paul pays for rent. How much does Paul pay for rent?

Answer

$750

2.2-115 §2.2 source ↗

Solve Number Word Problems

In the following exercises, solve each number word problem.

Laurie has $46,000 invested in stocks and bonds. The amount invested in stocks is $8,000 less than three times the amount invested in bonds. How much does Laurie have invested in bonds?

Answer

$13,500

2.2-117 §2.2 source ↗

Solve Percent Applications

In the following exercises, translate and solve.

ⓐ What number is 45% of 120? ⓑ 81 is 75% of what number? ⓐ What percent of 260 is 78?

Answer

ⓐ 54 ⓑ 108 ⓐ 30%

2.2-119 §2.2 source ↗

Solve Percent Applications

In the following exercises, translate and solve.

ⓐ 250% of 65 is what number? ⓑ 8.2% of what amount is $2.87? ⓐ 30 is what percent of 20?

Answer

ⓐ 162.5 ⓑ $35 ⓐ 150%

2.2-121 §2.2 source ↗

In the following exercises, solve.

Geneva treated her parents to dinner at their favorite restaurant. The bill was $74.25. Geneva wants to leave 16% of the total bill as a tip. How much should the tip be?

Answer

$ 11.88

2.2-123 §2.2 source ↗

In the following exercises, solve.

One serving of oatmeal has 8 grams of fiber, which is 33% of the recommended daily amount. What is the total recommended daily amount of fiber?

Answer

24.2 g

2.2-125 §2.2 source ↗

In the following exercises, solve.

A bacon cheeseburger at a popular fast food restaurant contains 2070 milligrams (mg) of sodium, which is 86% of the recommended daily amount. What is the total recommended daily amount of sodium?

Answer

2407 mg

2.2-127 §2.2 source ↗

In the following exercises, solve.

The nutrition fact sheet at a fast food restaurant says the fish sandwich has 380 calories, and 171 calories are from fat. What percent of the total calories is from fat?

Answer

45%

2.2-129 §2.2 source ↗

In the following exercises, solve.

Emma gets paid $3,000 per month. She pays $750 a month for rent. What percent of her monthly pay goes to rent?

Answer

25%

2.2-131 §2.2 source ↗

In the following exercises, solve.

Tamanika received a raise in her hourly pay, from $15.50 to $17.36. Find the percent change.

Answer

12%

2.2-133 §2.2 source ↗

In the following exercises, solve.

Annual student fees at the University of California rose from about $4,000 in 2000 to about $12,000 in 2010. Find the percent change.

Answer

200%

2.2-135 §2.2 source ↗

In the following exercises, solve.

A grocery store reduced the price of a loaf of bread from $2.80 to $2.73. Find the percent change.

Answer

−2.5 %

2.2-137 §2.2 source ↗

In the following exercises, solve.

Hernando’s salary was $49,500 last year. This year his salary was cut to $44,055. Find the percent change.

Answer

−11 %

2.2-139 §2.2 source ↗

In the following exercises, find ⓐ the amount of discount and ⓑ the sale price.

Janelle bought a beach chair on sale at 60% off. The original price was $44.95.

Answer

ⓐ $26.97 ⓑ $17.98

2.2-141 §2.2 source ↗

In the following exercises, find ⓐ the amount of discount and ⓑ the discount rate (Round to the nearest tenth of a percent if needed.)

Larry and Donna bought a sofa at the sale price of $1,344. The original price of the sofa was $1,920.

Answer

ⓐ $576 ⓑ 30%

2.2-143 §2.2 source ↗

In the following exercises, find ⓐ the amount of the mark-up and ⓑ the list price.

Daria bought a bracelet at original cost $16 to sell in her handicraft store. She marked the price up 45%. What was the list price of the bracelet?

Answer

ⓐ $7.20 ⓑ $23.20

2.2-145 §2.2 source ↗

In the following exercises, find ⓐ the amount of the mark-up and ⓑ the list price.

Tom paid $0.60 a pound for tomatoes to sell at his produce store. He added a 33% mark-up. What price did he charge his customers for the tomatoes?

Answer

ⓐ $0.20 ⓑ $0.80

2.2-147 §2.2 source ↗

Solve Simple Interest Applications

In the following exercises, solve.

Casey deposited $1,450 in a bank account that earned simple interest at an interest rate of 4%. How much interest was earned in two years?

Answer

$116

2.2-149 §2.2 source ↗

Solve Simple Interest Applications

In the following exercises, solve.

Robin deposited $31,000 in a bank account that earned simple interest at an interest rate of 5.2%. How much interest was earned in three years?

Answer

$4836

2.2-151 §2.2 source ↗

Solve Simple Interest Applications

In the following exercises, solve.

Hilaria borrowed $8,000 from her grandfather to pay for college. Five years later, she paid him back the $8,000, plus $1,200 interest. What was the rate of simple interest?

Answer

3%

2.2-153 §2.2 source ↗

Solve Simple Interest Applications

In the following exercises, solve.

Lebron lent his daughter $20,000 to help her buy a condominium. When she sold the condominium four years later, she paid him the $20,000, plus $3,000 interest. What was the rate of simple interest?

Answer

3.75 %

2.2-155 §2.2 source ↗

Solve Simple Interest Applications

In the following exercises, solve.

In 10 years, a bank account that paid 5.25% simple interest earned $18,375 interest. What was the principal of the account?

Answer

$35,000

2.2-157 §2.2 source ↗

Solve Simple Interest Applications

In the following exercises, solve.

Joshua’s computer loan statement said he would pay $1,244.34 in simple interest for a three-year loan at 12.4%. How much did Joshua borrow to buy the computer?

Answer

$3345

2.2-159 §2.2 source ↗

Solve Simple Interest Applications

In the following exercises, solve.

Tipping At the campus coffee cart, a medium coffee costs $1.65. MaryAnne brings $2.00 with her when she buys a cup of coffee and leaves the change as a tip. What percent tip does she leave?

Answer

21.2 %

2.2-161 §2.2 source ↗

Solve Simple Interest Applications

In the following exercises, solve.

What has been your past experience solving word problems? Where do you see yourself moving forward?

Answer

Answers will vary.

2.2-163 §2.2 source ↗

Solve Simple Interest Applications

In the following exercises, solve.

After returning from vacation, Alex said he should have packed 50% fewer shorts and 200% more shirts. Explain what Alex meant.

Answer

Answers will vary.

Be Prepared 2.7 §2.3 source ↗

Evaluate 2(x+3) when x=5.
If you missed this problem, review Example 1.6.
Example 1.6 in the book ↗

Answer

16

Be Prepared 2.8 §2.3 source ↗

The length of a rectangle is three less than the width. Let w represent the width. Write an expression for the length of the rectangle.
If you missed this problem, review Example 1.10.
Example 1.10 in the book ↗

Answer

w − 3

Be Prepared 2.9 §2.3 source ↗

Evaluate 12bh when b=14 and h=9.
If you missed this problem, review Example 1.33.
Example 1.33 in the book ↗

Answer

63

Try It 2.55 §2.3 source ↗

Use the formula A=12bh to solve for b.

Answer

b = 2 A h

Try It 2.56 §2.3 source ↗

Use the formula A=12bh to solve for h.

Answer

h = 2 A b

Try It 2.57 §2.3 source ↗

Solve the formula F=95C+32 for C.

Answer

C = 5 9 ( F − 32 )

Try It 2.58 §2.3 source ↗

Solve the formula A=12h(b+B) for b.

Answer

b = 2 A − B h h

Try It 2.59 §2.3 source ↗

Solve the formula A=P+Prt for t.

Answer

t = A − P P r

Try It 2.60 §2.3 source ↗

Solve the formula A=P+Prt for r.

Answer

r = A − P P t

Try It 2.61 §2.3 source ↗

Solve the formula 4x+7y=9 for y.

Answer

y = 9 − 4 x 7

Try It 2.62 §2.3 source ↗

Solve the formula 5x+8y=1 for y.

Answer

y = 1 − 5 x 8

Try It 2.63 §2.3 source ↗

The area of a triangular church window is 90 square meters. The base of the window is 15 meters. What is the window’s height?

Answer

The window’s height is 12 meters.

Try It 2.64 §2.3 source ↗

A triangular tent door has an area of 15 square feet. The height is five feet. What is the length of the base?

Answer

The length of the base is 6 feet.

Try It 2.65 §2.3 source ↗

The measure of one angle of a right triangle is 50 more than the measure of the smallest angle. Find the measures of all three angles.

Answer

The measures of the angles are 20°, 70°, and 90°.

Try It 2.66 §2.3 source ↗

The measure of one angle of a right triangle is 30 more than the measure of the smallest angle. Find the measures of all three angles.

Answer

The measures of the angles are 30°, 60°, and 90°.

Try It 2.67 §2.3 source ↗

Use the Pythagorean Theorem to find the length of the leg in the figure.

The figure is a right triangle with legs that are b units and 15 units, and a hypotenuse that is 17 units.

Answer

The length of the leg is 8.

Try It 2.68 §2.3 source ↗

Use the Pythagorean Theorem to find the length of the leg in the figure.

The figure is a right triangle with legs that are b units and 9 units, and a hypotenuse that is 15 units.

Answer

The length of the leg is 12.

Try It 2.69 §2.3 source ↗

The length of a rectangle is seven more than twice the width. The perimeter is 110 inches. Find the length and width.

Answer

The length is 39 inches and the width is 16 inches.

Try It 2.70 §2.3 source ↗

The width of a rectangle is eight yards less than twice the length. The perimeter is 86 yards. Find the length and width.

Answer

The length is 17 yards and the width is 26 yards.

Try It 2.71 §2.3 source ↗

One side of a triangle is seven inches more than the first side. The third side is four inches less than three times the first. The perimeter is 28 inches. Find the length of the three sides of the triangle.

Answer

The lengths of the sides of the triangle are 5, 11 and 12 inches.

Try It 2.72 §2.3 source ↗

One side of a triangle is three feet less than the first side. The third side is five feet less than twice the first. The perimeter is 20 feet. Find the length of the three sides of the triangle.

Answer

The lengths of the sides of the triangle are 4, 7 and 9 feet.

Try It 2.73 §2.3 source ↗

The perimeter of a rectangular swimming pool is 200 feet. The length is 40 feet more than the width. Find the length and width.

Answer

The length of the swimming pool is 70 feet and the width is 30 feet.

Try It 2.74 §2.3 source ↗

The length of a rectangular garden is 30 yards more than the width. The perimeter is 300 yards. Find the length and width.

Answer

The length of the garden is 90 yards and the width is 60 yards.

Try It 2.75 §2.3 source ↗

John puts the base of a 13-foot ladder five feet from the wall of his house as shown in the figure. How far up the wall does the ladder reach?

The figure is an illustration that shows a ladder placed against the wall of a house. The ladder forms a right triangle with the side of the house. The ladder is 13 feet long and the base of the ladder is 5 feet from the wall of the house.

Answer

The ladder reaches 12 feet.

Try It 2.76 §2.3 source ↗

Randy wants to attach a 17-foot string of lights to the top of the 15 foot mast of his sailboat, as shown in the figure. How far from the base of the mast should he attach the end of the light string?

The figure is an illustration of a sailboat that has a 15 foot mast. A string of lights that are 17 feet long are placed diagonally from the top of the mast.

Answer

He should attach the lights 8 feet from the base of the mast.

2.3-165 §2.3 source ↗

Solve a Formula for a Specific Variable

In the following exercises, solve the given formula for the specified variable.

Solve the formula C=πd for d.

Answer

d = C π

2.3-167 §2.3 source ↗

Solve a Formula for a Specific Variable

In the following exercises, solve the given formula for the specified variable.

Solve the formula V=LWH for L.

Answer

L = V W H

2.3-169 §2.3 source ↗

Solve a Formula for a Specific Variable

In the following exercises, solve the given formula for the specified variable.

Solve the formula A=12bh for b.

Answer

b = 2 A h

2.3-171 §2.3 source ↗

Solve a Formula for a Specific Variable

In the following exercises, solve the given formula for the specified variable.

Solve the formula
A=12d1d2 for d1.

Answer

d 1 = 2 A d 2

2.3-173 §2.3 source ↗

Solve a Formula for a Specific Variable

In the following exercises, solve the given formula for the specified variable.

Solve the formula
A= 12h(b1+b2) for b1.

Answer

b 1 = 2 A h − b 2

2.3-175 §2.3 source ↗

Solve a Formula for a Specific Variable

In the following exercises, solve the given formula for the specified variable.

Solve the formula
h=54t+12at2 for a.

Answer

a = 2 h − 108 t t 2

2.3-177 §2.3 source ↗

Solve a Formula for a Specific Variable

In the following exercises, solve the given formula for the specified variable.

Solve 180=a+b+c for a.

Answer

a = 180 − b − c

2.3-179 §2.3 source ↗

Solve a Formula for a Specific Variable

In the following exercises, solve the given formula for the specified variable.

Solve the formula
A=12pl+B for p.

Answer

p = 2 A − 2 B l

2.3-181 §2.3 source ↗

Solve a Formula for a Specific Variable

In the following exercises, solve the given formula for the specified variable.

Solve the formula
P=2L+2W for L.

Answer

L = P − 2 W 2

2.3-183 §2.3 source ↗

In the following exercises, solve for the formula for y.

Solve the formula
8x+y=15 for y.

Answer

y = 15 − 8 x

2.3-185 §2.3 source ↗

In the following exercises, solve for the formula for y.

Solve the formula
−4x+y=−6 for y.

Answer

y = −6 + 4 x

2.3-187 §2.3 source ↗

In the following exercises, solve for the formula for y.

Solve the formula
x−y=−4 for y.

Answer

y = 4 + x

2.3-189 §2.3 source ↗

In the following exercises, solve for the formula for y.

Solve the formula
4x+3y=7 for y.

Answer

y = 7 − 4 x 3

2.3-191 §2.3 source ↗

In the following exercises, solve for the formula for y.

Solve the formula
2x+3y=12 for y.

Answer

y = 12 − 2 x 3

2.3-193 §2.3 source ↗

In the following exercises, solve for the formula for y.

Solve the formula
3x−2y=18 for y.

Answer

y = 18 − 3 x −2

2.3-195 §2.3 source ↗

Use Formulas to Solve Geometry Applications

In the following exercises, solve using a geometry formula.

A triangular flag has area 0.75 square feet and height 1.5 foot. What is its base?

Answer

1 foot

2.3-197 §2.3 source ↗

Use Formulas to Solve Geometry Applications

In the following exercises, solve using a geometry formula.

What is the base of a triangle with area 207 square inches and height 18 inches?

Answer

23 inches

2.3-199 §2.3 source ↗

Use Formulas to Solve Geometry Applications

In the following exercises, solve using a geometry formula.

The two smaller angles of a right triangle have equal measures. Find the measures of all three angles.

Answer

45 ° , 45 ° , 90 °

2.3-201 §2.3 source ↗

Use Formulas to Solve Geometry Applications

In the following exercises, solve using a geometry formula.

The angles in a triangle are such that one angle is twice the smallest angle, while the third angle is three times as large as the smallest angle. Find the measures of all three angles.

Answer

30 ° , 60 ° , 90 °

2.3-203 §2.3 source ↗

In the following exercises, use the Pythagorean Theorem to find the length of the hypotenuse.

The figure is a right triangle with sides 9 units and 12 units.

Answer

15

2.3-205 §2.3 source ↗

In the following exercises, use the Pythagorean Theorem to find the length of the hypotenuse.

The figure is a right triangle with sides 15 units and 20 units.

Answer

25

2.3-207 §2.3 source ↗

In the following exercises, use the Pythagorean Theorem to find the length of the leg. Round to the nearest tenth if necessary.

The figure is a right triangle with sides 6 units and 10 units.

Answer

8

2.3-209 §2.3 source ↗

In the following exercises, use the Pythagorean Theorem to find the length of the leg. Round to the nearest tenth if necessary.

The figure is a right triangle with a side that is 5 units and a hypotenuse that is 13 units.

Answer

12

2.3-211 §2.3 source ↗

In the following exercises, use the Pythagorean Theorem to find the length of the leg. Round to the nearest tenth if necessary.

The figure is a right triangle with a side that is 8 units and a hypotenuse that is 13 units.

Answer

10.2

2.3-213 §2.3 source ↗

In the following exercises, use the Pythagorean Theorem to find the length of the leg. Round to the nearest tenth if necessary.

The figure is a right triangle with sides that are 5 units and 11 units.

Answer

9.8

2.3-215 §2.3 source ↗

In the following exercises, solve using a geometry formula.

The width of a rectangle is seven meters less than the length. The perimeter is 58 meters. Find the length and width.

Answer

18 meters, 11 meters

2.3-217 §2.3 source ↗

In the following exercises, solve using a geometry formula.

The width of the rectangle is 0.7 meters less than the length. The perimeter of a rectangle is 52.6 meters. Find the dimensions of the rectangle.

Answer

13.5 m, 12.8 m

2.3-219 §2.3 source ↗

In the following exercises, solve using a geometry formula.

The perimeter of a rectangle of 150 feet. The length of the rectangle is twice the width. Find the length and width of the rectangle.

Answer

25 ft, 50 ft

2.3-221 §2.3 source ↗

In the following exercises, solve using a geometry formula.

The length of the rectangle is three meters less than twice the width. The perimeter of a rectangle is 36 meters. Find the dimensions of the rectangle.

Answer

l = 11 m, w = 7 m

2.3-223 §2.3 source ↗

In the following exercises, solve using a geometry formula.

The perimeter of a triangle is 39 feet. One side of the triangle is one foot longer than the second side. The third side is two feet longer than the second side. Find the length of each side.

Answer

12 ft, 13 ft, 14 ft

2.3-225 §2.3 source ↗

In the following exercises, solve using a geometry formula.

One side of a triangle is twice the smallest side. The third side is five feet more than the shortest side. The perimeter is 17 feet. Find the lengths of all three sides.

Answer

3 ft, 6 ft, 8 ft

2.3-227 §2.3 source ↗

In the following exercises, solve using a geometry formula.

The perimeter of a rectangular field is 560 yards. The length is 40 yards more than the width. Find the length and width of the field.

Answer

120 yd, 160 yd

2.3-229 §2.3 source ↗

In the following exercises, solve using a geometry formula.

A rectangular parking lot has perimeter 250 feet. The length is five feet more than twice the width. Find the length and width of the parking lot.

Answer

40 ft, 85 ft

2.3-231 §2.3 source ↗

In the following exercises, solve. Approximate answers to the nearest tenth, if necessary.

A 13-foot string of lights will be attached to the top of a 12-foot pole for a holiday display as shown. How far from the base of the pole should the end of the string of lights be anchored?

The figure is an illustration that shows a 13 foot string of lights attached diagonally to the top of a 12 foot pole.

Answer

5 feet

2.3-233 §2.3 source ↗

In the following exercises, solve. Approximate answers to the nearest tenth, if necessary.

Chi is planning to put a diagonal path of paving stones through her flower garden as shown. The flower garden is a square with side 10 feet. What will the length of the path be?

The figure is an illustration of a diagonal path of stones through a square garden with 10 foot sides.The figure is an illustration of a diagonal path of stones through a square garden with 10 foot sides.

Answer

14.1 feet

2.3-235 §2.3 source ↗

In the following exercises, solve. Approximate answers to the nearest tenth, if necessary.

Converting temperature While on a tour in Greece, Tatyana saw that the temperature was 40° Celsius. Solve for F in the formula C=59(F−32) to find the Fahrenheit temperature.

Answer

104 ° F

2.3-237 §2.3 source ↗

In the following exercises, solve. Approximate answers to the nearest tenth, if necessary.

Christa wants to put a fence around her triangular flowerbed. The sides of the flowerbed are six feet, eight feet and 10 feet. How many feet of fencing will she need to enclose her flowerbed?

Answer

240 ft

2.3-239 §2.3 source ↗

In the following exercises, solve. Approximate answers to the nearest tenth, if necessary.

If you need to put tile on your kitchen floor, do you need to know the perimeter or the area of the kitchen? Explain your reasoning.

Answer

Answers will vary.

2.3-241 §2.3 source ↗

In the following exercises, solve. Approximate answers to the nearest tenth, if necessary.

Look at the two figures below.

A figure of a rectangle with a width that is 2 units and a length that is 8 units and a square with sides that are 4 units.

ⓐ Which figure looks like it has the larger area? Which looks like it has the larger perimeter?
ⓑ Now calculate the area and perimeter of each figure. Which has the larger area? Which has the larger perimeter?
ⓒ Were the results of part (b) the same as your answers in part (a)? Is that surprising to you?

Answer

ⓐ Answers will vary. ⓑ The areas are the same. The 2×8 rectangle has a larger perimeter than the 4×4 square.
ⓒ Answers will vary.

Be Prepared 2.10 §2.4 source ↗

Simplify: 0.25x+ 0.10(x+4).
If you missed this problem, review Example 1.52.
Example 1.52 in the book ↗

Answer

0.35 x + 0.4

Be Prepared 2.11 §2.4 source ↗

The number of adult tickets is three more than twice the number of children tickets. Let c represent the number of children tickets. Write an expression for the number of adult tickets.
If you missed this problem, review Example 1.11.
Example 1.11 in the book ↗

Answer

2 c + 3

Be Prepared 2.12 §2.4 source ↗

Convert 4.2% to a decimal.
If you missed this problem, review Example 1.40.
Example 1.40 in the book ↗

Answer

0.042

Try It 2.77 §2.4 source ↗

Jesse has $6.55 worth of quarters and nickels in his pocket. The number of nickels is five more than two times the number of quarters. How many nickels and how many quarters does Jesse have?

Answer

Jess has 41 nickels and 18 quarters.

Try It 2.78 §2.4 source ↗

Elane has $7.00 total in dimes and nickels in her coin jar. The number of dimes that Elane has is seven less than three times the number of nickels. How many of each coin does Elane have?

Answer

Elane has 22 nickels and 59 dimes.

Try It 2.79 §2.4 source ↗

Eric paid $19.88 for stamps. The number of 49-cent stamps was eight more than twice the number of 35-cent stamps. How many 49-cent stamps and how many 35-cent stamps did Eric buy?

Answer

Eric bought thirty-two 49-cent stamps and twelve 35-cent stamps.

Try It 2.80 §2.4 source ↗

Kailee paid $14.74 for stamps. The number of 49-cent stamps was four less than three times the number of 20-cent stamps. How many 49-cent stamps and how many 20-cent stamps did Kailee buy?

Answer

Kailee bought twenty-six 49-cent stamps and ten 20-cent stamps.

Try It 2.81 §2.4 source ↗

During her shift at the museum ticket booth, Leah sold 115 tickets for a total of $1,163. Adult tickets cost $12 and student tickets cost $5. How many adult tickets and how many student tickets did Leah sell?

Answer

84 adult tickets, 31 student tickets

Try It 2.82 §2.4 source ↗

Galen sold 810 tickets for his church’s carnival for a total revenue of $2,820. Children’s tickets cost $3 each and adult tickets cost $5 each. How many children’s tickets and how many adult tickets did he sell?

Answer

615 children’s tickets and 195 adult tickets

Try It 2.83 §2.4 source ↗

Orlando is mixing nuts and cereal squares to make a party mix. Nuts sell for $7 a pound and cereal squares sell for $4 a pound. Orlando wants to make 30 pounds of party mix at a cost of $6.50 a pound, how many pounds of nuts and how many pounds of cereal squares should he use?

Answer

Orlando mixed five pounds of cereal squares and 25 pounds of nuts.

Try It 2.84 §2.4 source ↗

Becca wants to mix fruit juice and soda to make a punch. She can buy fruit juice for $3 a gallon and soda for $4 a gallon. If she wants to make 28 gallons of punch at a cost of $3.25 a gallon, how many gallons of fruit juice and how many gallons of soda should she buy?

Answer

Becca mixed 21 gallons of fruit punch and seven gallons of soda.

Try It 2.85 §2.4 source ↗

An express train and a local train leave Pittsburgh to travel to Washington, D.C. The express train can make the trip in four hours and the local train takes five hours for the trip. The speed of the express train is 12 miles per hour faster than the speed of the local train. Find the speed of both trains.

Answer

The speed of the local train is 48 mph and the speed of the express train is 60 mph.

Try It 2.86 §2.4 source ↗

Jeromy can drive from his house in Cleveland to his college in Chicago in 4.5 hours. It takes his mother six hours to make the same drive. Jeromy drives 20 miles per hour faster than his mother. Find Jeromy’s speed and his mother’s speed.

Answer

Jeromy drove at a speed of 80 mph and his mother drove 60 mph.

Try It 2.87 §2.4 source ↗

Christopher and his parents live 115 miles apart. They met at a restaurant between their homes to celebrate his mother’s birthday. Christopher drove one and a half hours while his parents drove one hour to get to the restaurant. Christopher’s average speed was ten miles per hour faster than his parents’ average speed. What were the average speeds of Christopher and of his parents as they drove to the restaurant?

Answer

Christopher’s speed was 50 mph and his parents’ speed was 40 mph.

Try It 2.88 §2.4 source ↗

Ashley goes to college in Minneapolis, 234 miles from her home in Sioux Falls. She wants her parents to bring her more winter clothes, so they decide to meet at a restaurant on the road between Minneapolis and Sioux Falls. Ashley and her parents both drove two hours to the restaurant. Ashley’s average speed was seven miles per hour faster than her parents’ average speed. Find Ashley’s and her parents’ average speed.

Answer

Ashley’s parents drove 55 mph and Ashley drove 62 mph.

Try It 2.89 §2.4 source ↗

Pierre and Monique leave their home in Portland at the same time. Pierre drives north on the turnpike at a speed of 75 miles per hour while Monique drives south at a speed of 68 miles per hour. How long will it take them to be 429 miles apart?

Answer

Pierre and Monique will be 429 miles apart in 3 hours.

Try It 2.90 §2.4 source ↗

Thanh and Nhat leave their office in Sacramento at the same time. Thanh drives north on I-5 at a speed of 72 miles per hour. Nhat drives south on I-5 at a speed of 76 miles per hour. How long will it take them to be 330 miles apart?

Answer

Thanh and Nhat will be 330 miles apart in 2.2 hours.

Try It 2.91 §2.4 source ↗

Suzy takes 50 minutes to hike uphill from the parking lot to the lookout tower. It takes her 30 minutes to hike back down to the parking lot. Her speed going downhill is 1.2 miles per hour faster than her speed going uphill. Find Suzy’s uphill and downhill speeds.

Answer

Suzy’s speed uphill is 1.8 mph and downhill is three mph.

Try It 2.92 §2.4 source ↗

Llewyn takes 45 minutes to drive his boat upstream from the dock to his favorite fishing spot. It takes him 30 minutes to drive the boat back downstream to the dock. The boat’s speed going downstream is four miles per hour faster than its speed going upstream. Find the boat’s upstream and downstream speeds.

Answer

The boat’s speed upstream is eight mph and downstream is12 mph.

Try It 2.93 §2.4 source ↗

Hamilton loves to travel to Las Vegas, 255 miles from his home in Orange County. On his last trip, he left his house at 2:00 p.m. The first part of his trip was on congested city freeways. At 4:00 pm, the traffic cleared and he was able to drive through the desert at a speed 1.75 times as fast as when he drove in the congested area. He arrived in Las Vegas at 6:30 p.m. How fast was he driving during each part of his trip?

Answer

Hamilton drove 40 mph in the city and 70 mph in the desert.

Try It 2.94 §2.4 source ↗

Phuong left home on his bicycle at 10:00. He rode on the flat street until 11:15, then rode uphill until 11:45. He rode a total of 31 miles. His speed riding uphill was 0.6 times his speed on the flat street. Find his speed biking uphill and on the flat street.

Answer

Phuong rode uphill at a speed of 12 mph and on the flat street at 20 mph.

2.4-243 §2.4 source ↗

Solve Coin Word Problems

In the following exercises, solve each coin word problem.

Michaela has $2.05 in dimes and nickels in her change purse. She has seven more dimes than nickels. How many coins of each type does she have?

Answer

nine nickels, 16 dimes

2.4-245 §2.4 source ↗

Solve Coin Word Problems

In the following exercises, solve each coin word problem.

In a cash drawer there is $125 in $5 and $10 bills. The number of $10 bills is twice the number of $5 bills. How many of each type of bill is in the drawer?

Answer

ten $10 bills, five $5 bills

2.4-247 §2.4 source ↗

Solve Coin Word Problems

In the following exercises, solve each coin word problem.

Chi has $11.30 in dimes and quarters. The number of dimes is three more than three times the number of quarters. How many of each are there?

Answer

63 dimes, 20 quarters

2.4-249 §2.4 source ↗

Solve Coin Word Problems

In the following exercises, solve each coin word problem.

Mukul has $3.75 in quarters, dimes and nickels in his pocket. He has five more dimes than quarters and nine more nickels than quarters. How many of each coin are in his pocket?

Answer

16 nickels, 12 dimes, seven quarters

2.4-251 §2.4 source ↗

Solve Ticket and Stamp Word Problems

In the following exercises, solve each ticket or stamp word problem.

The first day of a water polo tournament the total value of tickets sold was $17,610. One-day passes sold for $20 and tournament passes sold for $30. The number of tournament passes sold was 37 more than the number of day passes sold. How many day passes and how many tournament passes were sold?

Answer

330 day passes, 367 tournament passes

2.4-253 §2.4 source ↗

Solve Ticket and Stamp Word Problems

In the following exercises, solve each ticket or stamp word problem.

Julie went to the post office and bought both $0.41 stamps and $0.26 postcards. She spent $51.40. The number of stamps was 20 more than twice the number of postcards. How many of each did she buy?

Answer

40 postcards, 100 stamps

2.4-255 §2.4 source ↗

Solve Ticket and Stamp Word Problems

In the following exercises, solve each ticket or stamp word problem.

Hilda has $210 worth of $10 and $12 stock shares. The number of $10 shares is five more than twice the number of $12 shares. How many of each type of share does she have?

Answer

15 $10 shares, five $12 shares

2.4-257 §2.4 source ↗

Solve Ticket and Stamp Word Problems

In the following exercises, solve each ticket or stamp word problem.

The ice rink sold 95 tickets for the afternoon skating session, for a total of $828. General admission tickets cost $10 each and youth tickets cost $8 each. How many general admission tickets and how many youth tickets were sold?

Answer

34 general, 61 youth

2.4-259 §2.4 source ↗

Solve Ticket and Stamp Word Problems

In the following exercises, solve each ticket or stamp word problem.

The box office sold 360 tickets to a concert at the college. The total receipts were $4,170. General admission tickets cost $15 and student tickets cost $10. How many of each kind of ticket was sold?

Answer

114 general, 246 student

2.4-261 §2.4 source ↗

Solve Mixture Word Problems

In the following exercises, solve each mixture word problem.

Macario is making 12 pounds of nut mixture with macadamia nuts and almonds. Macadamia nuts cost $9 per pound and almonds cost $5.25 per pound. How many pounds of macadamia nuts and how many pounds of almonds should Macario use for the mixture to cost $6.50 per pound to make?

Answer

Four pounds of macadamia nuts, eight pounds almonds

2.4-263 §2.4 source ↗

Solve Mixture Word Problems

In the following exercises, solve each mixture word problem.

Riley is planning to plant a lawn in his yard. He will need nine pounds of grass seed. He wants to mix Bermuda seed that costs $4.80 per pound with Fescue seed that costs $3.50 per pound. How much of each seed should he buy so that the overall cost will be $4.02 per pound?

Answer

3.6 lbs Bermuda seed, 5.4 lbs Fescue seed

2.4-265 §2.4 source ↗

Solve Mixture Word Problems

In the following exercises, solve each mixture word problem.

Vern sold his 1964 Ford Mustang for $55,000 and wants to invest the money to earn him 5.8% interest per year. He will put some of the money into Fund A that earns 3% per year and the rest in Fund B that earns 10% per year. How much should he invest into each fund if he wants to earn 5.8% interest per year on the total amount?

Answer

$33,000 in Fund A, $22,000 in Fund B

2.4-267 §2.4 source ↗

Solve Mixture Word Problems

In the following exercises, solve each mixture word problem.

Liam borrowed a total of $35,000 to pay for college. He pays his parents 3% interest on the $8,000 he borrowed from them and pays the bank 6.8% on the rest. What average interest rate does he pay on the total $35,000? (Round your answer to the nearest tenth of a percent.)

Answer

5.9 %

2.4-269 §2.4 source ↗

Solve Uniform Motion Applications

In the following exercises, solve.

Kathy and Cheryl are walking in a fundraiser. Kathy completes the course in 4.8 hours and Cheryl completes the course in eight hours. Kathy walks two miles per hour faster than Cheryl. Find Kathy’s speed and Cheryl’s speed.

Answer

Kathy 5 mph, Cheryl 3 mph

2.4-271 §2.4 source ↗

Solve Uniform Motion Applications

In the following exercises, solve.

A commercial jet and a private airplane fly from Denver to Phoenix. It takes the commercial jet 1.6 hours for the flight, and it takes the private airplane 2.6 hours. The speed of the commercial jet is 210 miles per hour faster than the speed of the private airplane. Find the speed of both airplanes to the nearest 10 mph.

Answer

commercial 550 mph, private plane 340 mph

2.4-273 §2.4 source ↗

Solve Uniform Motion Applications

In the following exercises, solve.

Charlie and Violet met for lunch at a restaurant between Memphis and New Orleans. Charlie had left Memphis and drove 4.8 hours towards New Orleans. Violet had left New Orleans and drove two hours towards Memphis, at a speed 10 miles per hour faster than Charlie’s speed. The distance between Memphis and New Orleans is 394 miles. Find the speed of the two drivers.

Answer

Violet 65 mph, Charlie 55 mph

2.4-275 §2.4 source ↗

Solve Uniform Motion Applications

In the following exercises, solve.

Ethan and Leo start riding their bikes at the opposite ends of a 65-mile bike path. After Ethan has ridden 1.5 hours and Leo has ridden two hours, they meet on the path. Ethan’s speed is six miles per hour faster than Leo’s speed. Find the speed of the two bikers.

Answer

Ethan 22 mph, Leo 16 mph

2.4-277 §2.4 source ↗

Solve Uniform Motion Applications

In the following exercises, solve.

DaMarcus and Fabian live 23 miles apart and play soccer at a park between their homes. DaMarcus rode his bike for three-quarters of an hour and Fabian rode his bike for half an hour to get to the park. Fabian’s speed was six miles per hour faster than DaMarcus’ speed. Find the speed of both soccer players.

Answer

DaMarcus 16 mph, Fabian 22 mph

2.4-279 §2.4 source ↗

Solve Uniform Motion Applications

In the following exercises, solve.

Matt and Chris leave their uncle’s house in Phoenix at the same time. Matt drives west on I-60 at a speed of 76 miles per hour. Chris drives east on I-60 at a speed of 82 miles per hour. How many hours will it take them to be 632 miles apart?

Answer

four hours

2.4-281 §2.4 source ↗

Solve Uniform Motion Applications

In the following exercises, solve.

Two boats leave the same dock in Cairo at the same time. One heads north on the Mississippi River while the other heads south. The northbound boat travels four miles per hour. The southbound boat goes eight miles per hour. How long will it take them to be 54 miles apart?

Answer

4.5 hours

2.4-283 §2.4 source ↗

Solve Uniform Motion Applications

In the following exercises, solve.

Julian rides his bike uphill for 45 minutes, then turns around and rides back downhill. It takes him 15 minutes to get back to where he started. His uphill speed is 3.2 miles per hour slower than his downhill speed. Find Julian’s uphill and downhill speed.

Answer

uphill 1.6 mph, downhill 4.8 mph

2.4-285 §2.4 source ↗

Solve Uniform Motion Applications

In the following exercises, solve.

It takes Darline 20 minutes to drive to work in light traffic. To come home, when there is heavy traffic, it takes her 36 minutes. Her speed in light traffic is 24 miles per hour faster than her speed in heavy traffic. Find her speed in light traffic and in heavy traffic.

Answer

light traffic 54 mph, heavy traffic 30 mph

2.4-287 §2.4 source ↗

Solve Uniform Motion Applications

In the following exercises, solve.

Aaron left at 9:15 to drive to his mountain cabin 108 miles away. He drove on the freeway until 10:45 and then drove on a mountain road. He arrived at 11:05. His speed on the freeway was three times his speed on the mountain road. Find Aaron’s speed on the freeway and on the mountain road.

Answer

freeway 67 mph, mountain road 22.3 mph

2.4-289 §2.4 source ↗

Solve Uniform Motion Applications

In the following exercises, solve.

Lizette is training for a marathon. At 7:00 she left her house and ran until 8:15 then she walked until 11:15. She covered a total distance of 19 miles. Her running speed was five miles per hour faster than her walking speed. Find her running and walking speeds.

Answer

running eight mph, walking three mph

2.4-291 §2.4 source ↗

Solve Uniform Motion Applications

In the following exercises, solve.

Sarah wants to arrive at her friend’s wedding at 3:00. The distance from Sarah’s house to the wedding is 95 miles. Based on usual traffic patterns, Sarah predicts she can drive the first 15 miles at 60 miles per hour, the next 10 miles at 30 miles per hour, and the remainder of the drive at 70 miles per hour.

ⓐ How long will it take Sarah to drive the first 15 miles?

ⓑ How long will it take Sarah to drive the next 10 miles?

ⓒ How long will it take Sarah to drive the rest of the trip?

ⓓ What time should Sarah leave her house?

Answer

ⓐ 15 minutes ⓑ 20 minutes ⓒ one hour (d) 1:25

2.4-293 §2.4 source ↗

Solve Uniform Motion Applications

In the following exercises, solve.

Do you find it helpful to use a table when solving coin problems? Why or why not?

Answer

Answers will vary.

2.4-295 §2.4 source ↗

Solve Uniform Motion Applications

In the following exercises, solve.

When solving a uniform motion problem, how does drawing a diagram of the situation help you?

Answer

Answers will vary.

Be Prepared 2.13 §2.5 source ↗

Translate from algebra to English: 15>x.
If you missed this problem, review Example 1.3.
Example 1.3 in the book ↗

Answer

15 is greater than x.

Be Prepared 2.14 §2.5 source ↗

Translate to an algebraic expression: 15 is less than x.
If you missed this problem, review Example 1.8.
Example 1.8 in the book ↗

Answer

15 < x

Try It 2.95 §2.5 source ↗

Graph each inequality on the number line and write in interval notation: ⓐ x>2 ⓑ x≤−1.5 ⓒ x≥34.

Answer

ⓐ

The graph of the inequality x is greater than 2 is indicated on a number line with a left parenthesis at 2 and shading to the right. The solution in interval notation is the interval from 2 to infinity enclosed within parentheses.

ⓑ

The graph of the inequality x is less than or equal to negative 1.5 is indicated on a number line with a right bracket at negative 1.5 and shading to the left. The solution in interval notation is the interval from negative infinity to negative 1.5 enclosed within a left parenthesis and right bracket.

ⓒ

The graph of the inequality x is greater than or rqual to three-fourths is indicated on a number line with a left bracket at three-fourths and shading to the right. The solution in interval notation is the interval from three-fourths to infinity enclosed within a left bracket and left parentheses.

Try It 2.96 §2.5 source ↗

Graph each inequality on the number line and write in interval notation: ⓐ x≤−4 ⓑ x≥0.5 ⓒ x<−23.

Answer

ⓐ

The graph of the inequality x is less than or equal to negative 4 is indicated on a number line with a right bracket at negative 4 and shading to the left. The solution in interval notation is the interval from negative infinity to negative 4 enclosed within an left parenthesis and right bracket.

ⓑ

The graph of the inequality x is greater than or equal to 0.5 is indicated on a number line with a left bracket at 0.5 and shading to the right. The solution in interval notation is the interval from 0.5 to infinity enclosed within a left bracket and right parenthesis.

ⓒ

The graph of the inequality x is less than negative two-thirds is indicated on a number line with a right parenthesis at negative two-thirds and shading to the left. The solution in interval notation is the interval from negative infinity to negative two-thirds enclosed within parentheses.

Try It 2.97 §2.5 source ↗

Graph each inequality on the number line and write in interval notation:

ⓐ −2< x< 1 ⓑ −5≤x<−4 ⓒ 1≤x≤4.25

Answer

ⓐ

Negative 2 is less x which is less than 1. There are open circles at negative 2 and 1 and shading between negative 2 and 1 on the number line. Put parentheses at negative 2 and 1. Write in interval notation.

ⓑ

Negative 5 is less than or equal to x which is less than negative 4. There is a closed circle at negative 6 and an open circle at negative 4 and shading between negative 5 and negative 4 on the number line. Put a bracket at negative 5 and a parenthesis at negative 4. Write in interval notation.

ⓒ

1 is less than or equal to x which is less than 4.25. There is closed circle at 1 and a closed circle at 4.25 and shading between 1 and 4.25 on the number line. Put brackets at 1 and 4.25. Write in interval notation.

Try It 2.98 §2.5 source ↗

Graph each inequality on the number line and write in interval notation:

ⓐ −6< x< 2 ⓑ −3≤x<−1 ⓒ 2.5≤x≤6

Answer

ⓐ

Negative 6 is less than x which is less than 2. There is an open circle at negative 6 and an open circle at 2 and shading between negative 6 and 2 on the number line. Put parentheses at negative 6 and 2. Write in interval notation.

ⓑ

Negative 3 is less than or equal to x which is less than negative 1. There is a closed circle at negative 3 and an open circle at negative 1 and shading between negative 3 and negative 1 on the number line. Put a bracket at negative 3 and a parenthesis at negative 1. Write in interval notation.

ⓒ

2.5 is less than or equal to x which is less thanor equal to 6. There is a closed circle at 2.5 and a closed circle at 6 and shading between 2.5 and 6 on the number line. Put brackets at 2.5 and 6. Write in interval notation.

Try It 2.99 §2.5 source ↗

Solve each inequality, graph the solution on the number line, and write the solution in interval notation:

ⓐ p−34≥16 ⓑ 9c>72 ⓒ 24≤38m

Answer

ⓐ

p is less than eleven-twelfths. The solution on the number line has a right bracket at eleven-twelfths with shading to the right. The solution in interval notation is, eleven-twelfths to infinity within a bracket and parenthesis.

ⓑ

c is less than 8. The solution on the number line has a left bracket at 8 with shading to the right. The solution in interval notation is, 8 to infinity within parentheses.

ⓒ

m is greater than or equal to 8. The solution on the number line has a right bracket at 64 with shading to the right. The solution in interval notation is, 64 to infinity within a bracket and parentheses.

Try It 2.100 §2.5 source ↗

Solve each inequality, graph the solution on the number line, and write the solution in interval notation:

ⓐ r−13≤712 ⓑ 12d≤​60 ⓒ −24<43n

Answer

ⓐ

r is less than or equal to eleven-twelfths. The solution on the number line has a left bracket at eleven-twelfths with shading to the left. The solution in interval notation is negative infinity to eleven-twelfths within a parenthesis and a bracket.

ⓑ

c is less than or equal to 5. The solution on the number line has a right bracket at 5 with shading to the left. The solution in interval notation is negative infinity to 5 within a parentheses and a bracket.

ⓒ

n is greater than negative 18. The solution on the number line has a left parenthesis at negative 18 with shading to the right. The solution in interval notation is negative 18 to infinity within parentheses.

Try It 2.101 §2.5 source ↗

Solve each inequality, graph the solution on the number line, and write the solution in interval notation:

ⓐ −8q<32 ⓑ k−12≤15.

Answer

ⓐ

q is greater than or equal to negative 4. The solution on the number line has a left parenthesis at negative 4 with shading to the right. The solution in interval notation is negative 4 to infinity within parentheses.

ⓑ

k is greater than or equal to negative 180. The solution on the number line has a left bracket at negative 180 with shading to the right. The solution in interval notation is negative 180 to infinity within a bracket and a parenthesis.

Try It 2.102 §2.5 source ↗

Solve each inequality, graph the solution on the number line, and write the solution in interval notation:

ⓐ −7r≤​−70 ⓑ u−4≥−16.

Answer

ⓐ

r is greater than or equal to 10. The solution on the number line has a left bracket at 10 with shading to the right. The solution in interval notation is 10 to infinity within a bracket and parenthesis.

ⓑ

u is less than or equal to 64. The solution on the number line has a right bracket at 64 with shading to the left. The solution in interval notation is negative infinity to 64 within parenthesis and a bracket.

Try It 2.103 §2.5 source ↗

Solve the inequality, graph the solution on the number line, and write the solution in interval notation: 3q≥7q−23.

Answer

q is less than or equal to 23 divided by 4. The solution on the number line has a right bracket at 23 divided by 4 with shading to the left. The solution in interval notation is negative infinity to 23 divided by 4 within a parenthesis and a bracket.

Try It 2.104 §2.5 source ↗

Solve the inequality, graph the solution on the number line, and write the solution in interval notation: 6x< 10x+ 19.

Answer

x is greater than negative 19 divided by 4. The solution on the number line has a left parenthesis at negative 19 divided by 4 with shading to the right. The solution in interval notation is negative 19 divided by 4 to infinity within parentheses.

Try It 2.105 §2.5 source ↗

Solve the inequality 9y+ 2(y+6)> 5y− 24, graph the solution on the number line, and write the solution in interval notation.

Answer

y is greater than negative 6. The solution on the number line has a left parenthesis at negative 6 with shading to the right. The solution in interval notation is negative 6 to infinity within parentheses.

Try It 2.106 §2.5 source ↗

Solve the inequality 6u+ 8(u−1)> 10u+ 32, graph the solution on the number line, and write the solution in interval notation.

Answer

u is greater than negative 10. The solution on the number line has a left parenthesis at 10 with shading to the right. The solution in interval notation is 10 to infinity within parentheses.

Try It 2.107 §2.5 source ↗

Solve the inequality 4b− 3(3−b)> 5(b−6)+ 2b, graph the solution on the number line, and write the solution in interval notation.

Answer

The inequality is an identity. Its solution on the number line is shaded for all values. The solution in interval notation is negative infinity to infinity within parentheses.

Try It 2.108 §2.5 source ↗

Solve the inequality 9h− 7(2−h)< 8(h+11)+ 8h, graph the solution on the number line, and write the solution in interval notation.

Answer

The inequality is an identity. Its solution on the number line is shaded for all values. The solution in interval notation is negative infinity to infinity within parentheses.

Try It 2.109 §2.5 source ↗

Solve the inequality 14x− 112x> 16x+ 78, graph the solution on the number line, and write the solution in interval notation.

Answer

The inequality is a contradiction. So, there is no solution. As a result, there is no graph on the number line or interval notation.

Try It 2.110 §2.5 source ↗

Solve the inequality 25z− 13z< 115z​+ 35, graph the solution on the number line, and write the solution in interval notation.

Answer

The inequality is an identity. Its solution on the number line is shaded for all values. The solution in interval notation is negative infinity to infinity within parentheses.

Try It 2.111 §2.5 source ↗

Translate and solve. Then graph the solution on the number line, and write the solution in interval notation.

Nineteen less than p is no less than 47.

Answer

p minus 19 is greater than or equal to 47. Its solution is p is greater than or equal to 66. The solution on the number line has a left bracket at 66 with shading to the right. The solution in interval notation is 66 to infinity within a bracket and a parenthesis.

Try It 2.112 §2.5 source ↗

Translate and solve. Then graph the solution on the number line, and write the solution in interval notation.

Four more than a is at most 15.

Answer

a plus 4 is less than or equal to 15. Its solution is a is less than or equal to 11. The solution on the number line has a right bracket at 11with shading to the left. The solution in interval notation is negative infinity to 11 within a parenthesis and bracket.

Try It 2.113 §2.5 source ↗

Angie has $20 to spend on juice boxes for her son’s preschool picnic. Each pack of juice boxes costs $2.63. What is the maximum number of packs she can buy?

Answer

Angie can buy 7 packs of juice.

Try It 2.114 §2.5 source ↗

Daniel wants to surprise his girlfriend with a birthday party at her favorite restaurant. It will cost $42.75 per person for dinner, including tip and tax. His budget for the party is $500. What is the maximum number of people Daniel can have at the party?

Answer

Daniel can have 11 people at the party.

Try It 2.115 §2.5 source ↗

Sergio and Lizeth have a very tight vacation budget. They plan to rent a car from a company that charges $75 a week plus $0.25 a mile. How many miles can they travel during the week and still keep within their $200 budget?

Answer

Sergio and Lizeth can travel no more than 500 miles.

Try It 2.116 §2.5 source ↗

Rameen’s heating bill is $5.42 per month plus $1.08 per therm. How many therms can Rameen use if he wants his heating bill to be a maximum of $87.50.

Answer

Rameen can use no more than 76 therms.

Try It 2.117 §2.5 source ↗

Caleb has a pet sitting business. He charges $32 per hour. His monthly expenses are $2,272. How many hours must he work in order to earn a profit of at least $800 per month?

Answer

Caleb must work at least 96 hours.

Try It 2.118 §2.5 source ↗

Elliot has a landscape maintenance business. His monthly expenses are $1,100. If he charges $60 per job, how many jobs must he do to earn a profit of at least $4,000 a month?

Answer

Elliot must work at least 85 jobs.

Try It 2.119 §2.5 source ↗

Brenda’s best friend is having a destination wedding and the event will require 3 nights in a hotel. Brenda has $500 in savings and can earn $15 an hour babysitting. She expects to pay $350 airfare, $375 for food and entertainment and $60 a night for her share of a hotel room. How many hours must she babysit to have enough money to pay for the trip?

Answer

Brenda must babysit at least 27 hours.

Try It 2.120 §2.5 source ↗

Josue wants to go on a 10-night road trip with friends next spring. It will cost him $180 for gas, $450 for food, and $49 per night to share a motel room. He has $520 in savings and can earn $30 per driveway shoveling snow. How many driveways must he shovel to have enough money to pay for the trip?

Answer

Josue must shovel at least 20 driveways.

2.5-297 §2.5 source ↗

Graph Inequalities on the Number Line

In the following exercises, graph each inequality on the number line and write in interval notation.


ⓐ x>3
ⓑ x≤−0.5
ⓒ x≥13

Answer


ⓐ

The solution for x is greater than 3 on a number line has a left bracket 3 with shading to the right. The solution in interval notation is 3 to infinity within parentheses.


ⓑ

The solution for x is less than or equal to negative 0.5 on a number line has a right bracket at negative 0.5 with shading to the left. The solution in interval notation is negative infinity to negative 0.5 within a parenthesis and a bracket.

ⓒ

The solution for x is greater than or equal to one-third on a number line has a left bracket at one-third with shading to the right. The solution in interval notation is one-third to infinity within a bracket and a parenthesis.

2.5-299 §2.5 source ↗

Graph Inequalities on the Number Line

In the following exercises, graph each inequality on the number line and write in interval notation.


ⓐ x≤5
ⓑ x≥−1.5
ⓒ x<−73

Answer


ⓐ

The solution for x is less than or equal to 5 on a number line has a right bracket with shading to the left. The solution in interval notation is negative infinity to 5 within a parenthesis and a bracket.


ⓑ

The solution for x is greater than or equal to negative 1.5 on a number line has a left bracket with shading to the right. The solution in interval notation is negative 1.5 to infinity within a bracket and a parenthesis.


ⓒ

The solution for x is less than negative seven-thirds on a number line has a right parenthesis with shading to the left. The solution in interval notation is negative infinity to negative seven-thirds within parentheses.

2.5-301 §2.5 source ↗

Graph Inequalities on the Number Line

In the following exercises, graph each inequality on the number line and write in interval notation.


ⓐ −2< x< 0
ⓑ −5≤x<−3
ⓒ 0≤x≤3.5

Answer


ⓐ

Negative 2 is less than x which is less than 0. There is an open circle at negative 2 and an open circle at 0 and shading between negative 2 and 0 on the number line. The interval notation is negative 2 and 0 within parentheses.


ⓑ

Negative 5 is less than or equal to x which is less than negative 3. There is a closed circle at negative 5 and an open circle at negative 3 and shading between negative 5 and negative 3 on the number line. The interval notation is negative 5 and negative 3 within a bracket and a parenthesis.


ⓒ

0 is less than or equal to x which is less than or equal to 3.5. There is a closed circle at 0 and a closed circle at 3.5 and shading between 0 and 3.5 on the number line. The interval notation is 0 and 3.5 within brackets.

2.5-303 §2.5 source ↗

Graph Inequalities on the Number Line

In the following exercises, graph each inequality on the number line and write in interval notation.


ⓐ −4< x< 2
ⓑ −5<x≤−2
ⓒ −3.75≤x≤0

Answer


ⓐ

Negative 4 is less than x which is less than 2. There is a open circle at negative 4 and an open circle at 2 and shading between negative 4 and 2 on the number line. The interval notation is negative 4 and 2 within parentheses.


ⓑ

Negative 5 is less than x which is less than or equal to 2. There is a open circle at negative 5 and a closed circle at negative 2 and shading between negative 5 and negative 2 on the number line. The interval notation is negative 5 and negative 2 within a parenthesis and a bracket.


ⓒ

Negative 3.75 is less than or equal to x which is less than or equal to 0. There is a closed circle at negative 3.75 and a closed circle at 0 and shading between negative 3.75 and 0 on the number line. The interval notation is negative 3.75 and 0 within brackets.

2.5-305 §2.5 source ↗

Solve Linear Inequalities

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.


ⓐ b+78≥16
ⓑ 6y<48
ⓒ 40<58k

Answer


ⓐ

The solution is b is greater than or equal to negative seventeen twenty-fourths. The solution on a number line has a left bracket negative seventeen twenty-fourths with shading to the right. The solution in interval notation is negative seventeen twenty-fourths to infinity within a bracket and a parenthesis.


ⓑ

The solution is y is less than 8. The solution on a number line has a right parenthesis at 8 with shading to the left. The solution in interval notation is negative infinity to 8 within parentheses.


ⓒ

The solution is k is greater than 64. The solution on a number line has a left parenthesis at 64 with shading to the right. The solution in interval notation is 64 to infinity within parentheses.

2.5-307 §2.5 source ↗

Solve Linear Inequalities

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.


ⓐ g− 1112< − 518
ⓑ 7s<−28
ⓒ 94g≤36

Answer


ⓐ

The solution is g is less than twenty-three thirty-sixths. The solution on a number line has a right parenthesis at twenty-three thirty-sixths with shading to the left. The solution in interval notation is negative infinity to twenty-three thirty-sixths within parentheses.


ⓑ

The solution is s is less than negative 4. The solution on a number line has a right parenthesis at negative 4 with shading to the left. The solution in interval notation is negative infinity to negative 4 within parentheses.


ⓒ

The solution is g is less than or equal to 16. The solution on a number line has a right bracket at 16 with shading to the left. The solution in interval notation is negative infinity to 16 within parenthesis and a bracket.

2.5-309 §2.5 source ↗

Solve Linear Inequalities

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.


ⓐ −8v≤96
ⓑ b−10≥30

Answer


ⓐ

The solution is v is greater than or equal to negative 12. The solution on a number line has a left bracket with shading to the right. The solution in interval notation is negative 12 to infinity within a bracket and a parenthesis.


ⓑ

The solution is b is less than or equal to negative 300. The solution on a number line has a right bracket at negative 300 with shading to the left. The solution in interval notation is negative infinity to negative 300 within a parenthesis and a bracket.

2.5-311 §2.5 source ↗

Solve Linear Inequalities

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.


ⓐ −7d>105
ⓑ −18>q−6

Answer


ⓐ

The solution is d is less than negative 15. The solution on a number line has a right parentheses with shading to the left. The solution in interval notation is negative infinity to negative 15 within parentheses.


ⓑ

The solution is q is greater than 108. The solution on a number line has a left parentheses at 108 with shading to the right. The solution in interval notation is 108 to infinity within parentheses.

2.5-313 §2.5 source ↗

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

5 u ≤ 8 u − 21

Answer


The solution is u is greater than or equal to 7. The solution on a number line has a left bracket at 7 with shading to the right. The solution in interval notation is 7 to infinity within a a bracket and a parenthesis.

2.5-315 §2.5 source ↗

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

9p> 14p− 18

Answer


The solution is p is less than eighteen fifths. The solution on a number line has a right parenthesis at eighteen fifths with shading to the left. The solution in interval notation negative infinity to eighteen fifths within parentheses.

2.5-317 §2.5 source ↗

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

9y+ 5(y+3)< 4y− 35

Answer


The solution is y is less than negative 5. The solution on a number line has a right parenthesis at negative 5 with shading to the left. The solution in interval notation is negative infinity to negative 5 within parentheses.

2.5-319 §2.5 source ↗

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

4k− (k−2)≥7k− 26

Answer


The solution is k is less than or equal to 7. The solution on a number line has a right bracket at 7with shading to the left. The solution in interval notation is negative infinity to 7 within a parenthesis and a bracket.

2.5-321 §2.5 source ↗

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

6n− 12(3−n)≤9(n−4)+ 9n

Answer


The inequality is an identity. Its solution on the number line is shaded for all values. The solution in interval notation is negative infinity to infinity within parentheses.

2.5-323 §2.5 source ↗

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

9u+ 5(2u−5)≥12(u−1)+ 7u

Answer


The inequality is a contradiction. So, there is no solution. As a result, there is no graph on the number line or interval notation.

2.5-325 §2.5 source ↗

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

4 5 h− 2 3 (h−9)≥ 1 15 (2h+90)

Answer


The inequality is an identity. Its solution on the number line is shaded for all values. The solution in interval notation is negative infinity to infinity within parentheses.

2.5-327 §2.5 source ↗

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

12v+ 3(4v−1)≤19(v−2)+ 5v

Answer


The inequality is a contradiction. So, there is no solution. As a result, there is no graph on the number line or interval notation.

2.5-329 §2.5 source ↗

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

35 k ≥ −77

Answer


The solution is k is greater than or equal to negative eleven fifthss. The solution on a number line has a left bracket at negative eleven fifths with shading to the right. The solution in interval notation is negative eleven fifths to negative infinity within a bracket and a parenthesis.

2.5-331 §2.5 source ↗

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

18q− 4(10−3q)< 5(6q−8)

Answer


The inequality is a contradiction. So, there is no solution. As a result, there is no graph on the number line or interval notation.

2.5-333 §2.5 source ↗

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

− 21 8 y ≤ − 15 28

Answer


The solution is y is greater than or equal to ten twenty-ninths. The solution on a number line has a left bracket at ten twenty-ninths with shading to the right. The solution in interval notation is ten twenty-ninths to infinity within a bracket and a parenthesis.

2.5-335 §2.5 source ↗

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

d + 29 > −61

Answer


The solution is g is greater than negative 90. The solution on a number line has a left parenthesis at negative 90 with shading to the right. The solution in interval notation is negative 90 to infinity within parentheses.

2.5-337 §2.5 source ↗

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

n 13 ≤ −6

Answer


The solution is n is less than or equal to negative 78. The solution on a number line has a right bracket at negative 78 with shading to the left. The solution in interval notation is negative infinity to negative 78 within a parenthesis and a bracket.

2.5-339 §2.5 source ↗

Translate to an Inequality and Solve

In the following exercises, translate and solve. Then graph the solution on the number line and write the solution in interval notation.

Six more than k exceeds 25.

Answer


The inequality is k plus 6 is greater than 25. Its solution is k is greater than 19. The solution on a number line has a left parenthesis at 19 with shading to the right. The solution in interval notation is 19 to infinity within parentheses.

2.5-341 §2.5 source ↗

Translate to an Inequality and Solve

In the following exercises, translate and solve. Then graph the solution on the number line and write the solution in interval notation.

Twelve less than x is no less than 21.

Answer


The inequality is x minus 12 is greater than or equal to 21. Its solution is x is greater than or equal to 33. The solution on a number line has a left bracket at 33 with shading to the right. The solution in interval notation is 33 to infinity within a bracket and a parenthesis.

2.5-343 §2.5 source ↗

Translate to an Inequality and Solve

In the following exercises, translate and solve. Then graph the solution on the number line and write the solution in interval notation.

Negative two times s is lower than 56.

Answer


The inequality is negative 2 s is less than 56. Its solution is s is greater than negative 28. The solution on a number line has a left parenthesis at negative 28 with shading to the right. The solution in interval notation is negative 28 to infinity within parentheses.

2.5-345 §2.5 source ↗

Translate to an Inequality and Solve

In the following exercises, translate and solve. Then graph the solution on the number line and write the solution in interval notation.

Fifteen less than a is at least −7.

Answer


The inequality is a minus 15 is greater than or equal to negative 7. Its solution is a is greater than or equal to 8. The solution on a number line has a left bracket at 8 with shading to the right. The solution in interval notation is 8 to infinity within a bracket and a parenthesis.

2.5-347 §2.5 source ↗

Solve Applications with Linear Inequalities

In the following exercises, solve.

The elevator in Yehire’s apartment building has a sign that says the maximum weight is 2100 pounds. If the average weight of one person is 150 pounds, how many people can safely ride the elevator?

Answer

A maximum of 14 people can safely ride in the elevator.

2.5-349 §2.5 source ↗

Solve Applications with Linear Inequalities

In the following exercises, solve.

Arleen got a $20 gift card for the coffee shop. Her favorite iced drink costs $3.79. What is the maximum number of drinks she can buy with the gift card?

Answer

five drinks

2.5-351 §2.5 source ↗

Solve Applications with Linear Inequalities

In the following exercises, solve.

Ryan charges his neighbors $17.50 to wash their car. How many cars must he wash next summer if his goal is to earn at least $1,500?

Answer

86 cars

2.5-353 §2.5 source ↗

Solve Applications with Linear Inequalities

In the following exercises, solve.

Kimuyen needs to earn $4,150 per month in order to pay all her expenses. Her job pays her $3,475 per month plus 4% of her total sales. What is the minimum Kimuyen’s total sales must be in order for her to pay all her expenses?

Answer

$16,875

2.5-355 §2.5 source ↗

Solve Applications with Linear Inequalities

In the following exercises, solve.

Nataly is considering two job offers. The first job would pay her $83,000 per year. The second would pay her $66,500 plus 15% of her total sales. What would her total sales need to be for her salary on the second offer be higher than the first?

Answer

$110,000

2.5-357 §2.5 source ↗

Solve Applications with Linear Inequalities

In the following exercises, solve.

Kiyoshi’s phone plan costs $17.50 per month plus $0.15 per text message. What is the maximum number of text messages Kiyoshi can use so the phone bill is no more than $56.60?

Answer

260 messages

2.5-359 §2.5 source ↗

Solve Applications with Linear Inequalities

In the following exercises, solve.

Kellen wants to rent a banquet room in a restaurant for her cousin’s baby shower. The restaurant charges $350 for the banquet room plus $32.50 per person for lunch. How many people can Kellen have at the shower if she wants the maximum cost to be $1,500?

Answer

35 people

2.5-361 §2.5 source ↗

Solve Applications with Linear Inequalities

In the following exercises, solve.

Noe installs and configures software on home computers. He charges $125 per job. His monthly expenses are $1,600. How many jobs must he work in order to make a profit of at least $2,400?

Answer

32 jobs

2.5-363 §2.5 source ↗

Solve Applications with Linear Inequalities

In the following exercises, solve.

Melissa makes necklaces and sells them online. She charges $88 per necklace. Her monthly expenses are $3,745. How many necklaces must she sell if she wants to make a profit of at least $1,650?

Answer

62 necklaces

2.5-365 §2.5 source ↗

Solve Applications with Linear Inequalities

In the following exercises, solve.

Cesar is planning a four-day trip to visit his friend at a college in another state. It will cost him $198 for airfare, $56 for local transportation, and $45 per day for food. He has $189 in savings and can earn $35 for each lawn he mows. How many lawns must he mow to have enough money to pay for the trip?

Answer

seven lawns

2.5-367 §2.5 source ↗

Solve Applications with Linear Inequalities

In the following exercises, solve.

Eun-Kyung works as a tutor and earns $60 per hour. She has $792 in savings. She is planning an anniversary party for her parents. She would like to invite 40 guests. The party will cost her $1,520 for food and drinks and $150 for the photographer. She will also have a favor for each of the guests, and each favor will cost $7.50. How many hours must she tutor to have enough money for the party?

Answer

20 hours

2.5-369 §2.5 source ↗

Solve Applications with Linear Inequalities

In the following exercises, solve.

Maximum weight on a boat In 2004, a water taxi sank in Baltimore harbor and five people drowned. The water taxi had a maximum capacity of 3,500 pounds (25 people with average weight 140 pounds). The average weight of the 25 people on the water taxi when it sank was 168 pounds per person. What should the maximum number of people of this weight have been?

Answer

20 people

2.5-371 §2.5 source ↗

Solve Applications with Linear Inequalities

In the following exercises, solve.

Shower budget Penny is planning a baby shower for her daughter-in-law. The restaurant charges $950 for up to 25 guests, plus $31.95 for each additional guest. How many guests can attend if Penny wants the total cost to be no more than $1,500?

Answer

42 guests

2.5-373 §2.5 source ↗

Solve Applications with Linear Inequalities

In the following exercises, solve.

Explain why it is necessary to reverse the inequality when solving n−3<12.

Answer

Answers will vary.

2.5-375 §2.5 source ↗

Solve Applications with Linear Inequalities

In the following exercises, solve.

Find out how many units you have left, after this term, to achieve your college goal and estimate the number of units you can take each term in college. Calculate the number of terms it will take you to achieve your college goal by writing an appropriate inequality and then solving it. Is this an acceptable number of terms until you meet your goal? What are some ways you could accelerate this process?

Answer

Answers will vary.

Be Prepared 2.15 §2.6 source ↗

Simplify: 25(x+10).
If you missed this problem, review Example 1.51.
Example 1.51 in the book ↗

Answer

2 5 x + 4

Be Prepared 2.16 §2.6 source ↗

Simplify: −(x−4).
If you missed this problem, review Example 1.54.
Example 1.54 in the book ↗

Answer

− x + 4

Try It 2.121 §2.6 source ↗

Solve the compound inequality. Graph the solution and write the solution in interval notation: 4x−7<9 and 5x+8≥3.

Answer

The solution is negative 1 is less than or equal to x which is less than 4. On a number line it is shown with a closed circle at negative 1 and an open circle at 4 with shading in between the closed and open circles. Its interval notation is negative 1 to 4 within a bracket and a parenthesis.

Try It 2.122 §2.6 source ↗

Solve the compound inequality. Graph the solution and write the solution in interval notation: 3x−4<5 and 4x+9≥1.

Answer

The solution is negative 2 is less than or equal to x which is less than 3. On a number line it is shown with a closed circle at negative 2 and an open circle at 3 with shading in between the closed and open circles. Its interval notation is negative 2 to 3 within a bracket and a parenthesis.

Try It 2.123 §2.6 source ↗

Solve the compound inequality. Graph the solution and write the solution in interval notation: 2(3x+1)≤20 and 4(x−1)< 2.

Answer

The solution is x is less than three-halves. On a number line it is shown with an open circle at three-halves with shading to its left. Its interval notation is negative infinity to three-halves within a parentheses.

Try It 2.124 §2.6 source ↗

Solve the compound inequality. Graph the solution and write the solution in interval notation: 5(3x−1)≤10 and 4(x+3)< 8.

Answer

The solution is x is less than negative 1. On a number line it is shown with an open circle at 1 with shading to its left. Its interval notation is negative infinity to negative 1 within parentheses.

Try It 2.125 §2.6 source ↗

Solve the compound inequality. Graph the solution and write the solution in interval notation: 14x−3≥−1 and −3(x−2)≥2.

Answer

The inequality is a contradiction. So, there is no solution. As a result, there is no graph of the number line or interval notation.

Try It 2.126 §2.6 source ↗

Solve the compound inequality. Graph the solution and write the solution in interval notation: 15x−5≥−3 and −4(x−1)≥−2.

Answer

The inequality is a contradiction. So, there is no solution. As a result, there is no graph or the number line or interval notation.

Try It 2.127 §2.6 source ↗

Solve the compound inequality. Graph the solution and write the solution in interval notation: −5≤4x− 1< 7.

Answer

The solution is negative 1 is less than or equal to x which is less than 2. Its graph has a closed circle at negative 1 and an open circle at 2 with shading between the closed and open circles. Its interval notation is negative 1 to 2 within a bracket and a parenthesis.

Try It 2.128 §2.6 source ↗

Solve the compound inequality. Graph the solution and write the solution in interval notation: −3< 2x− 5≤1.

Answer

The solution is 1 is less than x which is less than or equal to 3. Its graph has an open circle at 1 and a closed circle at 3 with shading between the closed and open circles. Its interval notation is negative 1 to 3 within a parenthesis and a bracket.

Try It 2.129 §2.6 source ↗

Solve the compound inequality. Graph the solution and write the solution in interval notation: 1−2x≤−3 or 7+3x≤4.

Answer

The solution is x is greater than or equal to 2 or x is less than or equal to 1. The graph of the solutions on a number line has a closed circle at negative 1 and shading to the left and a closed circle at 2 with shading to the right. The interval notation is the union of negative infinity to negative 1 within a parenthesis and a bracket and 2 and infinity within a bracket and a parenthesis.

Try It 2.130 §2.6 source ↗

Solve the compound inequality. Graph the solution and write the solution in interval notation: 2−5x≤−3 or 5+2x≤3.

Answer

The solution is x is greater than or equal to 1 or x is less than or equal to negative 1. The graph of the solutions on a number line has a closed circle at negative 1 and shading to the left and a closed circle at 1 with shading to the right. The interval notation is the union of negative infinity to negative 1 within a parenthesis and a bracket and 1 and infinity within a bracket and a parenthesis.

Try It 2.131 §2.6 source ↗

Solve the compound inequality. Graph the solution and write the solution in interval notation: 35x−7≤−1 or 13(x+6)≥−2.

Answer

The solution is an identity. Its solution on the number line is shaded for all values. The solution in interval notation is negative infinity to infinity within parentheses.

Try It 2.132 §2.6 source ↗

Solve the compound inequality. Graph the solution and write the solution in interval notation: 34x−3≤3 or 25(x+10)≥0.

Answer

The solution is an identity. Its solution on the number line is shaded for all values. The solution in interval notation is negative infinity to infinity within parentheses.

Try It 2.133 §2.6 source ↗

Due to the drought in California, many communities now have tiered water rates. There are different rates for Conservation Usage, Normal Usage and Excessive Usage. The usage is measured in the number of hundred cubic feet (hcf) the property owner uses.

During the summer, a property owner will pay $24.72 plus $1.32 per hcf for Conservation Usage. The bill for Conservation Usage would be between or equal to $31.32 and $52.12. How many hcf can the owner use if she wants her usage to stay in the conservation range?

Answer

The homeowner can use 5–20 hcf and still fall within the “conservation usage” billing range.

Try It 2.134 §2.6 source ↗

Due to the drought in California, many communities have tiered water rates. There are different rates for Conservation Usage, Normal Usage and Excessive Usage. The usage is measured in the number of hundred cubic feet (hcf) the property owner uses.

During the winter, a property owner will pay $24.72 plus $1.54 per hcf for Normal Usage. The bill for Normal Usage would be between or equal to $49.36 and $86.32. How many hcf will he be allowed to use if he wants his usage to stay in the normal range?

Answer

The homeowner can use 16–40 hcf and still fall within the “normal usage” billing range.

2.6-377 §2.6 source ↗

Solve Compound Inequalities with “and”

In the following exercises, solve each inequality, graph the solution, and write the solution in interval notation.

x≤4 and x>−2

Answer

The solution is negative 2 is less than x which is less than or equal to 4. Its graph has an open circle at 1negative 2 and a closed circle at 4 with shading between the open and closed circles. Its interval notation is negative 2 to 4 within a parenthesis and a bracket.

2.6-379 §2.6 source ↗

Solve Compound Inequalities with “and”

In the following exercises, solve each inequality, graph the solution, and write the solution in interval notation.

x>−6 and x<−3

Answer

The solution is negative 6 is less than x which is less than negative 3. Its graph has an open circle at negative 6 and an open circle at negative 3 with shading between open circles. Its interval notation is negative 6 to negative 3 within parentheses.

2.6-381 §2.6 source ↗

Solve Compound Inequalities with “and”

In the following exercises, solve each inequality, graph the solution, and write the solution in interval notation.

4x−1<7 and 2x+8≥4

Answer

The solution is negative 2 is less than or equal to x which is less than 2. Its graph has a closed circle at negative 2 and an open circle at 2 with shading between the closed and open circles. Its interval notation is negative 2 to 2 within a bracket and a parenthesis.

2.6-383 §2.6 source ↗

Solve Compound Inequalities with “and”

In the following exercises, solve each inequality, graph the solution, and write the solution in interval notation.

4x−2≤4 and
7x−1>−8

Answer

The solution is negative 1 is less than x which is less than or equal to three-halves. Its graph has an open circle at negative 1 and a closed circle at three-halves with shading between the open and closed circles. Its interval notation is negative 1 to three-halves within a parenthesis and a bracket.

2.6-385 §2.6 source ↗

Solve Compound Inequalities with “and”

In the following exercises, solve each inequality, graph the solution, and write the solution in interval notation.

7x−8<6 and
5x+7>−3

Answer

The solution is negative 2 is less than x which is less than 2. Its graph has an open circle at negative 2 and an open circle at 2 with shading between the open circles. Its interval notation is negative 2 to 2 within parentheses.

2.6-387 §2.6 source ↗

Solve Compound Inequalities with “and”

In the following exercises, solve each inequality, graph the solution, and write the solution in interval notation.

5(3x−2)≤5 and
3(x+3)<3

Answer

The solution is x is less than negative 2. Its graph has an open circle at negative 2 and is shaded to the left. Its interval notation is negative infinity to negative 2 within parentheses.

2.6-389 §2.6 source ↗

Solve Compound Inequalities with “and”

In the following exercises, solve each inequality, graph the solution, and write the solution in interval notation.

−3(x+4)< 0 and
−1(3x−1)≤7

Answer

The solution is x is greater than or equal to negative 2. Its graph has a closed circle at negative 2 and is shaded to the right. Its interval notation is negative 2 to infinity within a bracket and a parenthesis.

2.6-391 §2.6 source ↗

Solve Compound Inequalities with “and”

In the following exercises, solve each inequality, graph the solution, and write the solution in interval notation.

34(x−8)≤3 and
15(x−5)≤3

Answer

The solution is x is less than or equal to 12. Its graph has a closed circle at 12 and is shaded to the left. Its interval notation is negative infinity to 12 within a parenthesis and a bracket.

2.6-393 §2.6 source ↗

Solve Compound Inequalities with “and”

In the following exercises, solve each inequality, graph the solution, and write the solution in interval notation.

34x−5≥−2 and
−3(x+1)≥6

Answer

The solution is a contradiction. So, there is no solution. As a result, there is no graph or the number line or interval notation.

2.6-395 §2.6 source ↗

Solve Compound Inequalities with “and”

In the following exercises, solve each inequality, graph the solution, and write the solution in interval notation.

12(x−6)+ 2< −5 and
4−23x<6

Answer

The solution is a contradiction. So, there is no solution. As a result, there is no graph or the number line or interval notation.

2.6-397 §2.6 source ↗

Solve Compound Inequalities with “and”

In the following exercises, solve each inequality, graph the solution, and write the solution in interval notation.

−3< 2x− 5≤1

Answer

The solution is 1 is less than x which is less than or equal to 3. Its graph has an open circle at 1 and a closed circle at 3 and is shaded between the open and closed circles. Its interval notation is 1 to 3 within a parenthesis and a bracket.

2.6-399 §2.6 source ↗

Solve Compound Inequalities with “and”

In the following exercises, solve each inequality, graph the solution, and write the solution in interval notation.

−1< 3x+ 2< 8

Answer

The solution is negative 1 is less than x which is less than 2. Its graph has an open circle at negative 1 an open circle at 2 and is shaded between. Its interval notation is negative 1 to 2 within parentheses.

2.6-401 §2.6 source ↗

Solve Compound Inequalities with “and”

In the following exercises, solve each inequality, graph the solution, and write the solution in interval notation.

−6≤4x− 2< −2

Answer

The solution is negative 1 is less than or equal to x which is less than or 0. Its graph has a closed circle at negative 1 and an open circle at 0 and is shaded between the closed and open circles. Its interval notation is negative 1 to 0 within a bracket and a parenthesis.

2.6-403 §2.6 source ↗

Solve Compound Inequalities with “or”

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

x≤−4 or x>−3

Answer

The solution is x is less than or equal to negative 4 or x is greater than negative 3. The graph of the solutions on a number line has a closed circle at negative 4 and shading to the left and an open circle at negative 3 with shading to the right. The interval notation is the union of negative infinity to negative 4 within a parenthesis and a bracket and negative 3 and infinity within parentheses.

2.6-405 §2.6 source ↗

Solve Compound Inequalities with “or”

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

x<0 or x≥4

Answer

The solution is x is less than 0 or x is greater than or equal to 2. The graph of the solutions on a number line has an open circle at 0 and shading to the left and a closed circle at 4 with shading to the right. The interval notation is the union of negative infinity to 0 within parentheses and 4 to infinity within a bracket and parenthesis.

2.6-407 §2.6 source ↗

Solve Compound Inequalities with “or”

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

4−3x≤−2 or
2x−1≤−5

Answer

The solution is x is less than or equal to negative 2 or x is greater than or equal to 2. The graph of the solutions on a number line has a closed circle at negative 2 and shading to the left and a closed circle at 2 with shading to the right. The interval notation is the union of negative infinity to negative 2 within a parenthesis and a bracket and 2 to infinity within a bracket and a parenthesis.

2.6-409 §2.6 source ↗

Solve Compound Inequalities with “or”

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

3(2x−3)< −5 or
4x−1>3

Answer

The solution is x is less than two-thirds or x is greater than 1. The graph of the solutions on a number line has an open circle at two-thirds and shading to the left and an open circle at 1 with shading to the right. The interval notation is the union of negative infinity to two-thirds within parentheses and 1 and infinity within parentheses.

2.6-411 §2.6 source ↗

Solve Compound Inequalities with “or”

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

23x−3>5 or 3(5−x)>6

Answer

The solution is x is less than 3 or x is greater than 12. The graph of the solutions on a number line has an open circle at 3 and shading to the left and an open circle at 12 with shading to the right. The interval notation is the union of negative infinity to 3 within parentheses and 12 and infinity within parentheses.

2.6-413 §2.6 source ↗

Solve Compound Inequalities with “or”

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

2(x+3)≥0 or
3(x+4)≤6

Answer

The solution is an identity. Its solution on the number line is shaded for all values. The solution in interval notation is negative infinity to infinity within parentheses.

2.6-415 §2.6 source ↗

Solve Compound Inequalities with “or”

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

34x+2≤−1 or
12(x+8)≥−3

Answer

The solution is an identity. Its solution on the number line is shaded for all values. The solution in interval notation is negative infinity to infinity within parentheses.

2.6-417 §2.6 source ↗

Mixed practice

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

6(2x−1)> 6 and
5(x+2)≥0

Answer

The solution is x is less than 1. Its graph has an open circle at negative 1 is shaded to the right. Its interval notation is 1 to infinity within parentheses.

2.6-419 §2.6 source ↗

Mixed practice

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

12x−5≤3 or
14(x−8)≥−3

Answer

The solution is an identity. Its solution on the number line is shaded for all values. The solution in interval notation is negative infinity to infinity within parentheses.

2.6-421 §2.6 source ↗

Mixed practice

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

15(x−5)+ 6< 4 and
3−23x<5

Answer

The inequality is a contradiction. So, there is no solution. As a result, there is no graph on the number line or interval notation.

2.6-423 §2.6 source ↗

Mixed practice

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

6x−3≤1 and
5x−1>−6

Answer

The solution is negative 1 is less than x which is less than or equal to two-thirds. Its graph has an open circle at negative 1 and a closed circle at two-thirds and is shaded between the open and closed circles. Its interval notation is negative 1 to two-thirds within a parenthesis and a bracket.

2.6-425 §2.6 source ↗

Mixed practice

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

−5 ≤ 3 x − 2 ≤ 4

Answer

The solution is negative 1 is less than or equal to x which is less than 2. Its graph has a closed circle at negative 1 and a closed circle at 2 and is shaded between the closed circles. Its interval notation is negative 1 to 4 within brackets.

2.6-427 §2.6 source ↗

Solve Applications with Compound Inequalities

In the following exercises, solve.

Gregory is thinking of a number and he wants his sister Lauren to guess the number. His first clue is that six less than twice his number is between four and forty-two. Write a compound inequality that shows the range of numbers that Gregory might be thinking of.

Answer

5 ≤ n ≤ 24

2.6-429 §2.6 source ↗

Solve Applications with Compound Inequalities

In the following exercises, solve.

Elouise is creating a rectangular garden in her back yard. The length of the garden is 12 feet. The perimeter of the garden must be at least 36 feet and no more than 48 feet. Use a compound inequality to find the range of values for the width of the garden.

Answer

6 ≤ w ≤ 12

2.6-431 §2.6 source ↗

Solve Applications with Compound Inequalities

In the following exercises, solve.

Body Mass Index (BMI) is a measure of body fat is determined using your height and weight.

ⓐ Let x be your BMI. Research and then write the compound inequality to show the BMI range for you to be considered normal weight.

ⓑ Research a BMI calculator and determine your BMI. Is it a solution to the inequality in part (a)?

Answer

ⓐ answers vary ⓑ answers vary

2.6-433 §2.6 source ↗

Solve Applications with Compound Inequalities

In the following exercises, solve.

Explain the steps for solving the compound inequality 2−7x≥−5 or 4(x−3)+ 7> 3.

Answer

Answers will vary.

Be Prepared 2.17 §2.7 source ↗

Evaluate: −|7|.
If you missed this problem, review Example 1.12.
Example 1.12 in the book ↗

Answer

− 7

Be Prepared 2.18 §2.7 source ↗

Fill in <,>, or = for each of the following pairs of numbers.
ⓐ |−8|___− |−8| ⓑ 12___−|−12| ⓒ |−6|___−6 ⓓ −(−15)___− |−15|
If you missed this problem, review Example 1.12.
Example 1.12 in the book ↗

Answer

a. >; b. >; c. >; d. >

Be Prepared 2.19 §2.7 source ↗

Simplify: 14− 2|8− 3(4−1)|.
If you missed this problem, review Example 1.13.
Example 1.13 in the book ↗

Answer

12

Try It 2.135 §2.7 source ↗

Solve: ⓐ |x|=2 ⓑ |y|=−4 ⓒ |z|=0

Answer

ⓐ ±2 ⓑ no solution ⓒ 0

Try It 2.136 §2.7 source ↗

Solve: ⓐ |x|=11 ⓑ |y|=−5 ⓒ |z|=0

Answer

ⓐ ±11 ⓑ no solution ⓒ 0

Try It 2.137 §2.7 source ↗

Solve: |3x−5|−1=6.

Answer

x = 4 , x = − 2 3

Try It 2.138 §2.7 source ↗

Solve: |4x−3|−5=2.

Answer

x = −1 , x = 5 2

Try It 2.139 §2.7 source ↗

Solve: 3|x−4|−4=8.

Answer

x = 8 , x = 0

Try It 2.140 §2.7 source ↗

Solve: 2|x−5|+3=9.

Answer

x = 8 , x = 2

Try It 2.141 §2.7 source ↗

Solve: |34x− 5|+ 9= 4.

Answer

No solution

Try It 2.142 §2.7 source ↗

Solve: |56x+ 3|+ 8= 6.

Answer

No solution

Try It 2.143 §2.7 source ↗

Solve: |7x− 3|= |3x+ 7|.

Answer

x=−25, x=52

Try It 2.144 §2.7 source ↗

Solve: |6x− 5|= |3x+ 4|.

Answer

x=3, x=19

Try It 2.145 §2.7 source ↗

Graph the solution and write the solution in interval notation: |x|<9.

Answer

The solution is negative 9 is less than x which is less than 9. The number line shows open circles at negative 9 and 9 with shading in between the circles. The interval notation is negative 9 to 9 within parentheses.

Try It 2.146 §2.7 source ↗

Graph the solution and write the solution in interval notation: |x|<1.

Answer

The solution is negative 1 is less than x which is less than 1. The number line shows open circles at negative 1 and 1 with shading in between the circles. The interval notation is negative 1 to 1 within parentheses.

Try It 2.147 §2.7 source ↗

Solve |2x−1|≤5. Graph the solution and write the solution in interval notation:

Answer

The solution is negative 2 is less than or equal to x which is less than or equal to 3. The number line shows closed circles at negative 2 and 3 with shading between the circles. The interval notation is negative 2 to 3 within brackets.

Try It 2.148 §2.7 source ↗

Solve |4x−5|≤3. Graph the solution and write the solution in interval notation:

Answer

The solution is one-half is less than or equal to x which is less than or equal to 2. The number line shows closed circles at one-half and 2 with shading between the circles. The interval notation is one-half to 2 within brackets.

Try It 2.149 §2.7 source ↗

Solve |x|>2. Graph the solution and write the solution in interval notation.

Answer

The solution is x is less than negative 2 or x is greater than 2. The number line shows an open circle at negative 2 with shading to its left and an open circle at 2 with shading to its right. The interval notation is the union of negative infinity to negative 2 within parentheses and 2 to infinity within parentheses.

Try It 2.150 §2.7 source ↗

Solve |x|>1. Graph the solution and write the solution in interval notation.

Answer

The solution is x is less than negative 1 or x is greater than 1. The number line shows an open circle at negative 1 with shading to its left and an open circle at 1 with shading to its right. The interval notation is the union of negative infinity to negative 1 within parentheses and 1 to infinity within parentheses.

Try It 2.151 §2.7 source ↗

Solve |4x−3|≥5. Graph the solution and write the solution in interval notation.

Answer

The solution is x is less than or equal to negative one-half or x is greater than or equal 2. The number line shows a closed circle at negative one-half with shading to its left and a closed circle at 2 with shading to its right. The interval notation is the union of negative infinity to negative one-half within a parenthesis and a bracket and 2 to infinity within a bracket and a parenthesis

Try It 2.152 §2.7 source ↗

Solve |3x−4|≥2. Graph the solution and write the solution in interval notation.

Answer

The solution is x is less than or equal to two-thirds or x is greater than or equal 2. The number line shows a closed circle at two-thirds with shading to its left and a closed circle at 2 with shading to its right. The interval notation is the union of negative infinity to two-thirds within a parenthesis and a bracket and 2 to infinity within a bracket and a parenthesis.

Try It 2.153 §2.7 source ↗

The ideal diameter of a rod needed for a machine is 80 mm. The actual diameter can vary from the ideal diameter by 0.009 mm. What range of diameters will be acceptable to the customer without causing the rod to be rejected?

Answer

The diameter of the rod can be between 79.991 and 80.009 mm.

Try It 2.154 §2.7 source ↗

The ideal diameter of a rod needed for a machine is 75 mm. The actual diameter can vary from the ideal diameter by 0.05 mm. What range of diameters will be acceptable to the customer without causing the rod to be rejected?

Answer

The diameter of the rod can be between 74.95 and 75.05 mm.

2.7-435 §2.7 source ↗

Solve Absolute Value Equations

In the following exercises, solve.

ⓐ |x|=4 ⓑ |y|=−5 ⓒ |z|=0

Answer

ⓐ x=4,x=−4 ⓑ no solution ⓒ z=0

2.7-437 §2.7 source ↗

Solve Absolute Value Equations

In the following exercises, solve.

ⓐ |x|=3 ⓑ |y|=−1 ⓒ |z|=0

Answer

ⓐ x=3,x=−3 ⓑ no solution ⓒ z=0

2.7-439 §2.7 source ↗

Solve Absolute Value Equations

In the following exercises, solve.

| 4 x − 1 | − 3 = 0

Answer

x = 1 , x = − 1 2

2.7-441 §2.7 source ↗

Solve Absolute Value Equations

In the following exercises, solve.

| 4 x + 7 | + 2 = 5

Answer

x = −1 , x = − 5 2

2.7-443 §2.7 source ↗

Solve Absolute Value Equations

In the following exercises, solve.

3 | x − 4 | + 2 = 11

Answer

x = 7 , x = 1

2.7-445 §2.7 source ↗

Solve Absolute Value Equations

In the following exercises, solve.

3 | x + 2 | − 5 = 4

Answer

x = 1 , x = −5

2.7-447 §2.7 source ↗

Solve Absolute Value Equations

In the following exercises, solve.

−3|x− 4|+ 4= −5

Answer

x = 7 , x = 1

2.7-449 §2.7 source ↗

Solve Absolute Value Equations

In the following exercises, solve.

| 3 5 x − 2 | + 5 = 2

Answer

no solution

2.7-451 §2.7 source ↗

Solve Absolute Value Equations

In the following exercises, solve.

| 1 4 x + 3 | + 3 = 1

Answer

no solution

2.7-453 §2.7 source ↗

Solve Absolute Value Equations

In the following exercises, solve.

|4x+ 3|= |2x+ 1|

Answer

x = −1 , x = − 2 3

2.7-455 §2.7 source ↗

Solve Absolute Value Equations

In the following exercises, solve.

|6− x|= |3− 2x|

Answer

x = −3 , x = 3

2.7-457 §2.7 source ↗

Solve Absolute Value Inequalities with “less than”

In the following exercises, solve each inequality. Graph the solution and write the solution in interval notation.

| x | < 1

Answer

The solution is negative 1 is less than x which is less than 1. The number line shows an open circle at negative 1, an open circle at 1, and shading between the circles. The interval notation is negative 1 to 1 within parentheses.

2.7-459 §2.7 source ↗

Solve Absolute Value Inequalities with “less than”

In the following exercises, solve each inequality. Graph the solution and write the solution in interval notation.

| x | ≤ 3

Answer

The solution is negative 3 is less than or equal to x which is less than or equal to 3. The number line shows a closed circle at negative 3, a closed circle at 3, and shading between the circles. The interval notation is negative 3 to 3 within brackets.

2.7-461 §2.7 source ↗

Solve Absolute Value Inequalities with “less than”

In the following exercises, solve each inequality. Graph the solution and write the solution in interval notation.

| 2 x − 5 | ≤ 3

Answer

The solution is 1 is less than or equal to x which is less than or equal to 4. The number line shows a closed circle at 1, a closed circle at 4, and shading between the circles. The interval notation is 1 to 4 within brackets.

2.7-463 §2.7 source ↗

Solve Absolute Value Inequalities with “less than”

In the following exercises, solve each inequality. Graph the solution and write the solution in interval notation.

|3x− 7|+ 3< 1

Answer

The solution is a contradiction. So, there is no solution. As a result, there is no graph or the number line or interval notation.

2.7-465 §2.7 source ↗

Solve Absolute Value Inequalities with “less than”

In the following exercises, solve each inequality. Graph the solution and write the solution in interval notation.

| 6 x − 5 | < 7

Answer

The solution is negative one-third is less than x which is less than 2. The number line shows an open circle at negative one-half, an open circle at 2, and shading between the circles. The interval notation is negative one-third to 2 within parentheses.

2.7-467 §2.7 source ↗

Solve Absolute Value Inequalities with “less than”

In the following exercises, solve each inequality. Graph the solution and write the solution in interval notation.

| 5 x + 1 | ≤ −2

Answer

The solution is a contradiction. So, there is no solution. As a result, there is no graph or the number line or interval notation.

2.7-469 §2.7 source ↗

Solve Absolute Value Inequalities with “greater than”

In the following exercises, solve each inequality. Graph the solution and write the solution in interval notation.

| x | > 6

Answer

The solution is x is less than negative 6 or x is greater than 6. The number line shows an open circle at negative 6 with shading to its left and an open circle at 6 with shading to its right. The interval notation is the union of negative infinity to negative 6 within parentheses and 6 to infinity within parentheses

2.7-471 §2.7 source ↗

Solve Absolute Value Inequalities with “greater than”

In the following exercises, solve each inequality. Graph the solution and write the solution in interval notation.

| x | ≥ 5

Answer

The solution is x is less then or equal to negative 5 or x is greater than or equal to 5. The number line shows an open circle at negative 5 with shading to its left and an open circle at 5 with shading to its right. The interval notation is the union of negative infinity to negative 5 within parentheses and 5 to infinity within parentheses.

2.7-473 §2.7 source ↗

Solve Absolute Value Inequalities with “greater than”

In the following exercises, solve each inequality. Graph the solution and write the solution in interval notation.

| x − 5 | > − 2

Answer

The solution is an identity. Its solution on the number line is shaded for all values. The solution in interval notation is negative infinity to infinity within parentheses.

2.7-475 §2.7 source ↗

Solve Absolute Value Inequalities with “greater than”

In the following exercises, solve each inequality. Graph the solution and write the solution in interval notation.

| 2 x − 1 | > 5

Answer

The solution is x is less than negative 2 or x is greater than 3. The number line shows an open circle at negative 2 with shading to its left and an open circle at 3 with shading to its right. The interval notation is the union of negative infinity to negative 2 within parentheses and 3 to infinity within parentheses.

2.7-477 §2.7 source ↗

Solve Absolute Value Inequalities with “greater than”

In the following exercises, solve each inequality. Graph the solution and write the solution in interval notation.

| x − 7 | ≥ 1

Answer

The solution is x is less than or equal to 6 or x is greater than or equal to 8. The number line shows a closed circle at 6 with shading to its left and a closed circle at 8 with shading to its right. The interval notation is the union of negative infinity to 6 within parenthesis and a bracket and 8 to infinity within a bracket and a parenthesis.

2.7-479 §2.7 source ↗

Solve Absolute Value Inequalities with “greater than”

In the following exercises, solve each inequality. Graph the solution and write the solution in interval notation.

5 | x | + 6 ≥ 1

Answer

The solution is an identity. Its solution on the number line is shaded for all values. The solution in interval notation is negative infinity to infinity within parentheses.

2.7-481 §2.7 source ↗

In the following exercises, solve. For each inequality, also graph the solution and write the solution in interval notation.

|6x− 5|= |2x+ 3|

Answer

x = 2 , x = 1 4

2.7-483 §2.7 source ↗

In the following exercises, solve. For each inequality, also graph the solution and write the solution in interval notation.

| 2 x − 5 | + 2 = 3

Answer

x = 3 , x = 2

2.7-485 §2.7 source ↗

In the following exercises, solve. For each inequality, also graph the solution and write the solution in interval notation.

| 3 x + 1 | − 3 = 7

Answer

x = 3 , x = − 11 3

2.7-487 §2.7 source ↗

In the following exercises, solve. For each inequality, also graph the solution and write the solution in interval notation.

5 | 2 x − 1 | − 3 = 7

Answer

x = 3 2 , x = − 1 2

2.7-489 §2.7 source ↗

In the following exercises, solve. For each inequality, also graph the solution and write the solution in interval notation.

| x − 7 | > − 3

Answer

The solution is an identity. Its solution on the number line is shaded for all values. The solution in interval notation is negative infinity to infinity within parentheses.

2.7-491 §2.7 source ↗

Solve Applications with Absolute Value

In the following exercises, solve.

An organic juice bottler ideally produces 215,000 bottle per day. But this total can vary by as much as 7,500 bottles. What is the maximum and minimum expected production at the bottling company?

Answer

The minimum to maximum expected production is 207,500 to 2,225,000 bottles

2.7-493 §2.7 source ↗

Solve Applications with Absolute Value

In the following exercises, solve.

At Lilly’s Bakery, the ideal weight of a loaf of bread is 24 ounces. By law, the actual weight can vary from the ideal by 1.5 ounces. What range of weight will be acceptable to the inspector without causing the bakery being fined?

Answer

The acceptable weight is 22.5 to 25.5 ounces.

2.7-495 §2.7 source ↗

Solve Applications with Absolute Value

In the following exercises, solve.

In your own words, explain how to solve the absolute value inequality, |3x−2|≥4.

Answer

Answers will vary.

2.R-497 §2.R source ↗

Solve Equations Using the General Strategy for Solving Linear Equations

In the following exercises, determine whether each number is a solution to the equation.

−12n+ 5= 8n, n= − 5 4

Answer

no

2.R-499 §2.R source ↗

In the following exercises, solve each linear equation.

− ( s + 4 ) = 18

Answer

s = −22

2.R-501 §2.R source ↗

In the following exercises, solve each linear equation.

1 3 (6m+21)= m− 7

Answer

m = −14

2.R-503 §2.R source ↗

In the following exercises, solve each linear equation.

0.25(q−8)= 0.1(q+7)

Answer

q = 18

2.R-505 §2.R source ↗

In the following exercises, solve each linear equation.

5+ 7(2−5x)= 2(9x+1)− (13x−57)

Answer

x = −1

2.R-507 §2.R source ↗

In the following exercises, solve each linear equation.

2[−16+5(8k−6)]= 8(3−4k)− 32

Answer

k = 3 4

2.R-509 §2.R source ↗

Classify Equations

In the following exercises, classify each equation as a conditional equation, an identity, or a contradiction and then state the solution.

9u+ 32= 15(u−4)− 3(2u+21)

Answer

contradiction; no solution

2.R-511 §2.R source ↗

Solve Equations with Fraction or Decimal Coefficients

In the following exercises, solve each equation.

2 5 n − 1 10 = 7 10

Answer

n = 2

2.R-513 §2.R source ↗

Solve Equations with Fraction or Decimal Coefficients

In the following exercises, solve each equation.

1 2 (k+3)= 1 3 (k+16)

Answer

k = 23

2.R-515 §2.R source ↗

Solve Equations with Fraction or Decimal Coefficients

In the following exercises, solve each equation.

0.8x− 0.3= 0.7x+ 0.2

Answer

x = 5

2.R-517 §2.R source ↗

Use a Problem Solving Strategy for Word Problems

In the following exercises, solve using the problem solving strategy for word problems.

Three-fourths of the people at a concert are children. If there are 87 children, what is the total number of people at the concert?

Answer

There are 116 people.

2.R-519 §2.R source ↗

Solve Number Word Problems

In the following exercises, solve each number word problem.

The sum of a number and three is forty-one. Find the number.

Answer

38

2.R-521 §2.R source ↗

Solve Number Word Problems

In the following exercises, solve each number word problem.

One number is two more than four times another. Their sum is negative thirteen. Find the numbers.

Answer

−3 , −10

2.R-523 §2.R source ↗

Solve Number Word Problems

In the following exercises, solve each number word problem.

Find three consecutive even integers whose sum is 234.

Answer

76, 78, 80

2.R-525 §2.R source ↗

Solve Number Word Problems

In the following exercises, solve each number word problem.

Koji has $5,502 in his savings account. This is $30 less than six times the amount in his checking account. How much money does Koji have in his checking account?

Answer

$922

2.R-527 §2.R source ↗

Solve Percent Applications

In the following exercises, translate and solve.

12.5% of what number is 20?

Answer

160

2.R-529 §2.R source ↗

In the following exercises, solve.

The bill for Dino’s lunch was $19.45. He wanted to leave 20% of the total bill as a tip. How much should the tip be?

Answer

$ 3.89

2.R-531 §2.R source ↗

In the following exercises, solve.

Jaden earns $2,680 per month. He pays $938 a month for rent. What percent of his monthly pay goes to rent?

Answer

35%

2.R-533 §2.R source ↗

In the following exercises, solve.

Rowena’s monthly gasoline bill dropped from $83.75 last month to $56.95 this month. Find the percent change.

Answer

32%

2.R-535 §2.R source ↗

In the following exercises, solve.

Lacey bought a pair of boots on sale for $95. The original price of the boots was $200. Find ⓐ the amount of discount and ⓑ the discount rate. (Round to the nearest tenth of a percent, if needed.)

Answer

ⓐ $105 ⓑ 52.5%

2.R-537 §2.R source ↗

Solve Simple Interest Applications

In the following exercises, solve.

Winston deposited $3,294 in a bank account with interest rate 2.6% How much interest was earned in five years?

Answer

$428.22

2.R-539 §2.R source ↗

Solve Simple Interest Applications

In the following exercises, solve.

Jaime’s refrigerator loan statement said he would pay $1,026 in interest for a four-year loan at 13.5%. How much did Jaime borrow to buy the refrigerator?

Answer

$1,900

2.R-541 §2.R source ↗

Solve a Formula for a Specific Variable

In the following exercises, solve the formula for the specified variable.

Solve the formula
A=12d1d2 for d2.

Answer

d 2 = 2 A d 1

2.R-543 §2.R source ↗

Solve a Formula for a Specific Variable

In the following exercises, solve the formula for the specified variable.

Solve the formula
4x−3y=12 for y.

Answer

y = 4 x 3 − 4

2.R-545 §2.R source ↗

Use Formulas to Solve Geometry Applications

In the following exercises, solve using a geometry formula.

The measure of the smallest angle in a right triangle is 45° less than the measure of the next larger angle. Find the measures of all three angles.

Answer

22.5°, 67.5°, 90°

2.R-547 §2.R source ↗

Use Formulas to Solve Geometry Applications

In the following exercises, solve using a geometry formula.

Find the length of the hypotenuse.

The figure is a right triangle with a base of 10 units and a height of 24 units.

Answer

26

2.R-549 §2.R source ↗

Use Formulas to Solve Geometry Applications

In the following exercises, solve using a geometry formula.

Sergio needs to attach a wire to hold the antenna to the roof of his house, as shown in the figure. The antenna is eight feet tall and Sergio has 10 feet of wire. How far from the base of the antenna can he attach the wire? Approximate to the nearest tenth, if necessary.

The figure is a right triangle with a height of 8 feet and a hypotenuse of 10 feet.

Answer

6 feet

2.R-551 §2.R source ↗

Use Formulas to Solve Geometry Applications

In the following exercises, solve using a geometry formula.

The length of a rectangle is 12 cm more than the width. The perimeter is 74 cm. Find the length and the width.

Answer

24.5 cm, 12.5 cm

2.R-553 §2.R source ↗

Use Formulas to Solve Geometry Applications

In the following exercises, solve using a geometry formula.

The perimeter of a triangle is 35 feet. One side of the triangle is five feet longer than the second side. The third side is three feet longer than the second side. Find the length of each side.

Answer

9 ft, 14 ft, 12 ft

2.R-555 §2.R source ↗

Solve Coin Word Problems

In the following exercises, solve.

Lenny has $3.69 in pennies, dimes, and quarters. The number of pennies is three more than the number of dimes. The number of quarters is twice the number of dimes. How many of each coin does he have?

Answer

nine pennies, six dimes, 12 quarters

2.R-557 §2.R source ↗

Solve Ticket and Stamp Word Problems

In the following exercises, solve each ticket or stamp word problem.

125 tickets were sold for the jazz band concert for a total of $1,022. Student tickets cost $6 each and general admission tickets cost $10 each. How many of each kind of ticket were sold?

Answer

57 students, 68 general admission

2.R-559 §2.R source ↗

Solve Mixture Word Problems

In the following exercises, solve.

Marquese is making 10 pounds of trail mix from raisins and nuts. Raisins cost $3.45 per pound and nuts cost $7.95 per pound. How many pounds of raisins and how many pounds of nuts should Marquese use for the trail mix to cost him $6.96 per pound?

Answer

2.2 lbs of raisins, 7.8 lbs of nuts

2.R-561 §2.R source ↗

Solve Mixture Word Problems

In the following exercises, solve.

Enrique borrowed $23,500 to buy a car. He pays his uncle 2% interest on the $4,500 he borrowed from him, and he pays the bank 11.5% interest on the rest. What average interest rate does he pay on the total $23,500? (Round your answer to the nearest tenth of a percent.)

Answer

9.7 %

2.R-563 §2.R source ↗

Solve Uniform Motion Applications

In the following exercises, solve.

Louellen and Tracy met at a restaurant on the road between Chicago and Nashville. Louellen had left Chicago and drove 3.2 hours towards Nashville. Tracy had left Nashville and drove 4 hours towards Chicago, at a speed one mile per hour faster than Louellen’s speed. The distance between Chicago and Nashville is 472 miles. Find Louellen’s speed and Tracy’s speed.

Answer

Louellen 65 mph, Tracy 66 mph

2.R-565 §2.R source ↗

Solve Uniform Motion Applications

In the following exercises, solve.

Kyle rowed his boat upstream for 50 minutes. It took him 30 minutes to row back downstream. His speed going upstream is two miles per hour slower than his speed going downstream. Find Kyle’s upstream and downstream speeds.

Answer

upstream 3 mph, downstream 5 mph

2.R-567 §2.R source ↗

Solve Uniform Motion Applications

In the following exercises, solve.

Anthony drove from New York City to Baltimore, which is a distance of 192 miles. He left at 3:45 and had heavy traffic until 5:30. Traffic was light for the rest of the drive, and he arrived at 7:30. His speed in light traffic was four miles per hour more than twice his speed in heavy traffic. Find Anthony’s driving speed in heavy traffic and light traffic.

Answer

heavy traffic 32 mph, light traffic 68 mph

2.R-569 §2.R source ↗

Graph Inequalities on the Number Line

In the following exercises, graph the inequality on the number line and write in interval notation.

x ≥ −2.5

Answer

The solution is x is greater than or equal to negative 2.5. The number line shows a left bracket at negative 2.5 with shading to its right. The interval notation is negative 2.5 to infinity within a bracket and a parenthesis.

2.R-571 §2.R source ↗

Graph Inequalities on the Number Line

In the following exercises, graph the inequality on the number line and write in interval notation.

x > 2

Answer

The solution is x is greater than 2. The number line shows a left parenthesis at 2 with shading to its right. The interval notation is 2 to infinity within parentheses.

2.R-573 §2.R source ↗

Graph Inequalities on the Number Line

In the following exercises, graph the inequality on the number line and write in interval notation.

−5 ≤ x < − 3

Answer

The solution is negative 5 is less than or equal to x which is less than negative 3. The number line shows a closed circle at negative 5, an open circle at negative 3, and shading between the circles. The interval notation is negative 5 to negative 3 within a bracket and a parenthesis.

2.R-575 §2.R source ↗

Solve Linear Inequalities

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

n − 12 ≤ 23

Answer

The solution is n is less than or equal to 35. The number line shows a a right bracket at 35 with shading to its left. The interval notation is negative infinity to 35 within a parenthesis and a bracket.

2.R-577 §2.R source ↗

Solve Linear Inequalities

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

9 x > 54

Answer

The solution is x is greater than 6. The number line shows a left parenthesis at 6 with shading to its right. The interval notation is 6 to infinity within parentheses.

2.R-579 §2.R source ↗

Solve Linear Inequalities

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

6p> 15p− 30

Answer

The solution is p is less than ten-thirds. The number line shows a right parenthesis at ten-thirds with shading to its left. The interval notation is negative infinity to ten-thirds within parentheses.

2.R-581 §2.R source ↗

Solve Linear Inequalities

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

5n− 15(4−n)≤10(n−6)+ 10n

Answer

The solution is an identity. Its solution on the number line is shaded for all values. The solution in interval notation is negative infinity to infinity within parentheses.

2.R-583 §2.R source ↗

Translate Words to an Inequality and Solve

In the following exercises, translate and solve. Then write the solution in interval notation and graph on the number line.

Five more than z is at most 19.

Answer

The inequality is z plus 5 is less than or equal to 19. Its solution is z is less than or equal to 14. The number line shows a right bracket at 14 with shading to its left. The interval notation is negative infinity to 14 within a parenthesis and a bracket.

2.R-585 §2.R source ↗

Translate Words to an Inequality and Solve

In the following exercises, translate and solve. Then write the solution in interval notation and graph on the number line.

Nine times n exceeds 42.

Answer

The inequality is 9 n is greater than 42. Its solution is n is greater than fourteen-thirds. The number line shows a left parentheses at fourteen-thirds with shading to its right. The interval notation is fourteen-thirds to infinity within parentheses.

2.R-587 §2.R source ↗

Solve Applications with Linear Inequalities

In the following exercises, solve.

Julianne has a weekly food budget of $231 for her family. If she plans to budget the same amount for each of the seven days of the week, what is the maximum amount she can spend on food each day?

Answer

$33 per day

2.R-589 §2.R source ↗

Solve Applications with Linear Inequalities

In the following exercises, solve.

Briana has been offered a sales job in another city. The offer was for $42,500 plus 8% of her total sales. In order to make it worth the move, Briana needs to have an annual salary of at least $66,500. What would her total sales need to be for her to move?

Answer

at least $300,000

2.R-591 §2.R source ↗

Solve Applications with Linear Inequalities

In the following exercises, solve.

Costa is an accountant. During tax season, he charges $125 to do a simple tax return. His expenses for buying software, renting an office, and advertising are $6,000. How many tax returns must he do if he wants to make a profit of at least $8,000?

Answer

at least 112 jobs

2.R-593 §2.R source ↗

Solve Compound Inequalities with “and”

In each of the following exercises, solve each inequality, graph the solution, and write the solution in interval notation.

x≤5 and x>−3

Answer

The solution is negative 3 is less than x which is less than or equal to 5. The number line shows an open circle at negative 3 and a closed circle at 5. The interval notation is negative 3 to 5 within a parenthesis and a bracket.

2.R-595 §2.R source ↗

Solve Compound Inequalities with “and”

In each of the following exercises, solve each inequality, graph the solution, and write the solution in interval notation.

5(3x−2)≤5 and
4(x+2)<3

Answer

The solution is negative x is less than negative five-fourths. The number line shows an open circle at negative five-fourths with shading to its left. The interval notation is negative infinity to negative five-fourths within parentheses.

2.R-597 §2.R source ↗

Solve Compound Inequalities with “and”

In each of the following exercises, solve each inequality, graph the solution, and write the solution in interval notation.

34x−5≥−2 and
−3(x+1)≥6

Answer

The solution is a contradiction. So, there is no solution. As a result, there is no graph on the number line or interval notation

2.R-599 §2.R source ↗

Solve Compound Inequalities with “or”

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

5−2x≤−1 or
6+3x≤4

Answer

The solution is x is less than negative two-thirds or x is greater than or equal to 3. The number line shows a closed circle at negative two-thirds with shading to its left and a closed circle at 3 with shading to its right. The interval notation is the union of negative infinity to negative two-thirds within a parenthesis and a bracket and 3 to infinity within a bracket and a parenthesis.

2.R-601 §2.R source ↗

Solve Compound Inequalities with “or”

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

34x−2>4 or 4(2−x)>0

Answer

The solution is x is less than 2 or x is greater than 8. The number line shows an open circle at 2 with shading to its left and an open circle at 8 with shading to its right. The interval notation is the union of negative infinity to 8 within parentheses and 8 to infinity within parentheses.

2.R-603 §2.R source ↗

Solve Compound Inequalities with “or”

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

12x−3≤4 or
13(x−6)≥−2

Answer

The solution is an identity. Its solution on the number line is shaded for all values. The solution in interval notation is negative infinity to infinity within parentheses.

2.R-605 §2.R source ↗

Solve Applications with Compound Inequalities

In the following exercises, solve.

Elouise is creating a rectangular garden in her back yard. The length of the garden is 12 feet. The perimeter of the garden must be at least 36 feet and no more than 48 feet. Use a compound inequality to find the range of values for the width of the garden.

Answer

6 ≤ w ≤ 12

2.R-607 §2.R source ↗

Solve Absolute Value Equations

In the following exercises, solve.

| y | = −14

Answer

no solution

2.R-609 §2.R source ↗

Solve Absolute Value Equations

In the following exercises, solve.

| 3 x − 4 | + 5 = 7

Answer

x = 2 , x = 2 3

2.R-611 §2.R source ↗

Solve Absolute Value Equations

In the following exercises, solve.

−2|x− 3|+ 8= −4

Answer

x = 9 , x = −3

2.R-613 §2.R source ↗

Solve Absolute Value Equations

In the following exercises, solve.

|6x− 5|= |2x+ 3|

Answer

x = 2 , x = 1 4

2.R-615 §2.R source ↗

Solve Absolute Value Inequalities with “less than”

In the following exercises, solve each inequality. Graph the solution and write the solution in interval notation.

| 2 x − 5 | ≤ 3

Answer

The solution is 1 is less than or equal to x which is less than or equal to 4. The number line shows a closed circle at 1, a closed circle at 4, and shading in between the circles. The interval notation is 1 to 4 within brackets.

2.R-617 §2.R source ↗

Solve Absolute Value Inequalities with “less than”

In the following exercises, solve each inequality. Graph the solution and write the solution in interval notation.

| 5 x + 1 | ≤ −2

Answer

The solution is a contradiction. So, there is no solution. As a result, there is no graph or the number line or interval notation.

2.R-619 §2.R source ↗

Solve Absolute Value Inequalities with “greater than”

In the following exercises, solve. Graph the solution and write the solution in interval notation.

| x | ≥ 2

Answer

The solution is x is less than negative 2 or x is greater than 6. The number line shows a closed circle at negative 2 with shading to its left and a closed circle at 2 with shading to its right. The interval notation is the union of negative infinity to negative 2 within a parenthesis and a bracket and 2 to infinity within a bracket and a parenthesis.

2.R-621 §2.R source ↗

Solve Absolute Value Inequalities with “greater than”

In the following exercises, solve. Graph the solution and write the solution in interval notation.

| x − 7 | ≥ 1

Answer

The solution is x is less than or equal to 6 or x is greater than or equal to 8. The number line shows a closed circle at 6 with shading to its left and a closed circle at 8 with shading to its right. The interval notation is the union of negative infinity to negative 6 within a parenthesis and a bracket and 8 to infinity within a bracket and a parenthesis.

2.R-623 §2.R source ↗

Solve Applications with Absolute Value

In the following exercises, solve.

A craft beer brewer needs 215,000 bottle per day. But this total can vary by as much as 5,000 bottles. What is the maximum and minimum expected usage at the bottling company?

Answer

The minimum to maximum expected usage is 210,000 to 220,000 bottles

2.T-625 §2.T source ↗

In the following exercises, solve each equation.

−5 ( 2 x + 1 ) = 45

Answer

x = −5

2.T-627 §2.T source ↗

In the following exercises, solve each equation.

8(3a+5)− 7(4a−3)= 20− 3a

Answer

a = 41

2.T-629 §2.T source ↗

In the following exercises, solve each equation.

14n− 3(4n+5)= −9+ 2(n−8)

Answer

contradiction; no solution

2.T-631 §2.T source ↗

In the following exercises, solve each equation.

3 4 x− 2 3 = 1 2 x+ 5 6

Answer

x = 6

2.T-633 §2.T source ↗

In the following exercises, solve each equation.

|2x− 1|= |4x+ 3|

Answer

x = −2 , x = − 1 3

2.T-635 §2.T source ↗

In the following exercises, graph the inequality on the number line and write in interval notation.

x ≥ −3.5

Answer

The inequality is x is greater than or equal to negative 3.5. The number line shows a left bracket at negative 3.5 and shading to the right. The interval notation is negative 3.5 to infinity within a bracket and a parenthesis.

2.T-637 §2.T source ↗

In the following exercises, graph the inequality on the number line and write in interval notation.

−2 ≤ x < 5

Answer

The inequality is negative two is less than or equal to x which is less than 5. The number line shows a closed circle at negative 2 and an open circle at 5 with shading between the circles. The interval notation is negative 2 to 5 within a bracket and a parenthesis.

2.T-639 §2.T source ↗

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

3c− 10(c−2)< 5c+ 16

Answer

The solution is c is greater than one-third. The number line shows a left parenthesis at one-third with shading to its right. The interval notation is one-third to infinity within parentheses.

2.T-641 §2.T source ↗

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

3(2x−3)< −5 or
4x−1>3

Answer

The solution is x is less than two-thirds or x is greater than 1. The number line shows an open circle at two-thirds with shading to its left and an open circle at 1 with shading to its right. The interval notation is the union of negative infinity to two-thirds within parentheses and 1 to infinity within parentheses.

2.T-643 §2.T source ↗

In the following exercises, solve each inequality, graph the solution on the number line, and write the solution in interval notation.

| 4 x − 3 | ≥ 5

Answer

The solution is x is less than or equal to negative one-half or x is greater than or equal to 2. The number line shows a closed circle at negative one-half with shading to its left and a closed circle at 2 with shading to its right. The interval notation is the union of negative infinity to negative one-half within a parenthesis and bracket and 2 to infinity within a bracket and a parenthesis.

2.T-645 §2.T source ↗

In the following exercises, translate to an equation or inequality and solve.

Find the length of the missing side.

The figure is a right triangle with a base of 6 units and a height of 9 units.

Answer

10.8

2.T-647 §2.T source ↗

In the following exercises, translate to an equation or inequality and solve.

The sum of two consecutive odd integers is −112. Find the numbers.

Answer

−57 , −55

2.T-649 §2.T source ↗

In the following exercises, translate to an equation or inequality and solve.

Bonita has $2.95 in dimes and quarters in her pocket. If she has five more dimes than quarters, how many of each coin does she have?

Answer

12 dimes, seven quarters

2.T-651 §2.T source ↗

In the following exercises, translate to an equation or inequality and solve.

The measure of one angle of a triangle is twice the measure of the smallest angle. The measure of the third angle is three times the measure of the smallest angle. Find the measures of all three angles.

Answer

30 ° , 60 ° , 90 °

2.T-653 §2.T source ↗

In the following exercises, translate to an equation or inequality and solve.

Two planes leave Dallas at the same time. One heads east at a speed of 428 miles per hour. The other plane heads west at a speed of 382 miles per hour. How many hours will it take them to be 2,025 miles apart?

Answer

2.5 hours

2.T-655 §2.T source ↗

In the following exercises, translate to an equation or inequality and solve.

Sara has a budget of $1,000 for costumes for the 18 members of her musical theater group. If all the costumes are the same price, what is the maximum she can spend for each costume?

Answer

At most $55.56 per costume.

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Problems and answers are adapted from Intermediate Algebra 2e by Lynn Marecek and Andrea Honeycutt Mathis, OpenStax, and are used under the CC BY-NC-SA 4.0 licence. Access for free at https://openstax.org/books/intermediate-algebra-2e/pages/1-introduction. Illustrations: Copyright Rice University, OpenStax, under CC BY-NC-SA 4.0 license. This adaptation is released under the same licence, is non-commercial, and is neither affiliated with nor endorsed by OpenStax or Rice University.