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Skills Practice Skills Practice for Lesson 5.1

Name _____________________________________________ Date _________________________

Widgets, Dumbbells, and DumpstersMultiple Representations of Linear Functions

Vocabulary Write the term that best completes each statement.

1. A(n) is an equation whose graph is a straight line.

2. The letters “f(x)” can be used to name a function written in .

3. A(n) describes the location of any point on a coordinate grid.

4. All linear equations are also , except when they are in the form x � a,

where a represents any number.

Problem Set Write a linear equation to model each situation.

1. A carpenter charges a $75 flat fee plus $50 per hour. Write an equation to represent the

cost, c, to hire the carpenter for h hours.

c � 50h � 75

2. Marsha has $125 now and plans to save $35 per week. Write an equation to represent the

amount, s, that Marsha will have saved after w weeks.

3. Raul and his friends rent a sailboat for $15 per hour plus a basic fee of $50. Write an

equation that gives the total cost, c, to rent the boat for h hours.

4. Gail orders CDs for $8 each plus a total shipping cost of $5. Write an equation that gives

the total price, p, of her order if she orders n CDs.

5. A teacher starts the year with $600 for art supplies. He plans to spend $40 per week on

supplies. Write an equation to show the amount, d, that the teacher has left after w weeks.

6. A sales representative on a business trip is 550 miles from home. She estimates that she

can travel 50 miles per hour while driving home. Write an equation to show her distance

from home, d, after she has been driving for h hours.

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Complete the table of values for each linear equation.

7. y � 3x � 10 8. y � 8x � 3

x y x y

5 25 1

8 34 2

10 40 4

12 46 8

50 160 10

9. y � 50 � 2x 10. y � 14 � 4x

x y x y

0 1

3 3

5 5

10 10

12 20

Graph the points for each table of values. Draw a straight line through the points.

11. 12.

x 2 4 8 10 x 3 5 7 8

y 4 5 7 8 y 0 4 8 10

6

5

7

8

9

4

3

2

1

65 8 9721 3 4

y

x

6

5

7

8

9

4

3

2

1

65 8 9721 3 4

y

x

Chapter 5 ● Skills Practice 397

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13. 14.

x 0 1 3 4 x 0 2 6 8

y 8 6 2 0 y 4 3 1 0

6

5

7

8

9

4

3

2

1

65 8 9721 3 4

y

x

6

5

7

8

9

4

3

2

1

65 8 9721 3 4

y

x

15. 16.

x 1 3 4 9 x 0 2 5 7

y 5 5 5 5 y 8 8 8 8

6

5

7

8

9

4

3

2

1

65 8 9721 3 4

y

x

6

5

7

8

9

4

3

2

1

65 8 9721 3 4

y

x

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17. 18.

x 7 7 7 7 x 2 2 2 2

y 0 1 3 5 y 2 4 6 8

6

5

7

8

9

4

3

2

1

65 8 9721 3 4

y

x

6

5

7

8

9

4

3

2

1

65 8 9721 3 4

y

x

19. 20.

x 2 4 6 8 x 0 2 4 6

y 0 3 6 9 y 9 6 3 0

6

5

7

8

9

4

3

2

1

65 8 9721 3 4

y

x

6

5

7

8

9

4

3

2

1

65 8 9721 3 4

y

x

Chapter 5 ● Skills Practice 399

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Decide whether each graph represents a linear equation, a linear function, both, or neither.

21.

6

5

7

8

9

4

3

2

1

65 8 9721 3 4

y

x

22.

6

5

7

8

9

4

3

2

1

65 8 9721 3 4

y

x

both a linear equation and a linear function

23.

6

5

7

8

9

4

3

2

1

65 8 9721 3 4

y

x

24.

6

5

7

8

9

4

3

2

1

65 8 9721 3 4

y

x

25.

6

5

7

8

9

4

3

2

1

65 8 9721 3 4

y

x

26.

6

5

7

8

9

4

3

2

1

65 8 9721 3 4

y

x

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27.

6

5

7

8

9

4

3

2

1

65 8 9721 3 4

y

x

28.

6

5

7

8

9

4

3

2

1

65 8 9721 3 4

y

x

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Skills Practice Skills Practice for Lesson 5.2

Name _____________________________________________ Date _________________________

Selling BalloonsFinding Intercepts of a Graph

Vocabulary Explain how each pair of terms is related by identifying similarities and differences.

1. x-coordinate and y-coordinate

2. x-intercept and y-intercept

3. vertical line and horizontal line

4. x-axis and y-axis

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Problem Set Determine the x-intercept and the y-intercept for each graph.

1.

x5210 43

2

3

4

5

6

1

–1

–2

–1–2–3

y 2.

x

5 6 7 8210 43

2

3

4

5

6

1

–1

–2

y

x-intercept: 2; y-intercept: 5

3.

1

2

3

4

–1

–2

–3

–4

1 3 42–3–4 –2 –1

y

x0

4.

1

2

3

4

–1

–2

–3

–4

1 3 42–3–4 –2 –1

y

x0

Chapter 5 ● Skills Practice 403

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5.

1

2

3

4

–1

–2

–3

–4

–1 1 2–2–5–6 –4 –3

y

x0

6.

–2

–3

–1

1

–4

–5

–6

–7

4 6 75–1 1 2 3

y

x0

Determine the x-intercept of the graph of each equation.

7. y � 3x � 6 8. y � 2x � 8

0 � 3x � 6

6 � 3x

x � 2

9. 3x � 5y � 15 10. 6x � 2y � 30

Determine the y-intercept of the graph of each equation.

11. y � 8 � 3x 12. y � 4x � 1

y � 8 � 3(0)

y � 8

13. 2x � 5y � 10 14. 3y � 2x � 9

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Identify each intercept and explain what it means in terms of the problem situation.

15. To calculate the cost y of manufacturing x pens, a company uses the equation

y � 5000 � 2x. Identify and interpret the y-intercept.

The y-intercept is 5000. It shows the initial start-up cost before the cost per pen is added.

16. The cost y of renting a canoe can be shown by y � 25 � 10x, where x is the time in hours.

Identify and interpret the y-intercept.

17. An art teacher has $360 for supplies and plans to spend $18 per week. An equation for the

situation is y � 360 � 18x. Identify and interpret the x-intercept.

18. Alma wants to lose 30 pounds at the rate of 2 pounds per week. An equation for the

situation is y � 30 � 2x. Identify and interpret the x-intercept.

19. A bookstore has mysteries on sale for $2 each and biographies for $3 each. Greg has $30

to spend on books. An equation for the situation is 2x � 3y � 30. Identify and interpret both

intercepts.

20. Marge’s goal is to sell $100 worth of tickets to the school play. The tickets are $4 for

children and $10 for adults. An equation for the situation is 4x � 10y � 100. Identify and

interpret both intercepts.

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Skills Practice Skills Practice for Lesson 5.3

Name _____________________________________________ Date _________________________

Recycling and SavingFinding the Slope of a Line

Vocabulary Match each definition or description to its corresponding term.

1. comparison of two quantities written as a : b or as a fraction a. unit rate

2. describes a line that slants upward from left to right b. slope

3. difference in x-coordinates when computing slope c. vertical change

4. ratio of vertical change, to horizontal change, of a line d. horizontal change

5. a rate per one unit e. rate of change

6. describes a line that slants downward from left to right f. ratio

7. difference in y-coordinates when computing slope g. positive slope

8. ratio comparing amount of change in dependent variable with h. negative slope

amount of change in independent variable in a real-life situation

Problem Set Calculate each unit rate. Write each rate as a fraction.

1. It costs $2.24 to mail a package that weighs 16 ounces. Calculate the cost per ounce.

$2.24 � 16 � $0.14 $0.14 ______ 1 oz

2. It costs $3.95 for 5 pounds of bananas. Calculate the cost per banana.

3. It takes 5 hours to travel 260 miles. Calculate the miles traveled each hour.

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4. It takes 12 seconds to travel 540 meters. Calculate the number of meters traveled per second.

5. You can read 168 pages in 6 days. Calculate the number of pages read per day.

6. You save $625 in 5 months. Calculate the amount of money saved each month.

7. It takes 4 hours to run 26.2 miles. Calculate the number of miles ran per hour.

8. It takes 8 days to bicycle 683.2 miles. Calculate the number of miles bicycled per day.

9. 3.2 pounds of cherries cost $7.68. Calculate the cost per pound.

10. A package weighing 3.6 pounds costs $8.10 to mail. Calculate the cost per pound.

Determine whether the slope of the line in each graph is positive, negative, zero, or undefined.

11.

–1

–2

1

2

–3

–4

–5

–6

y

1 3 42–3–4 –2 –1 x0

12.

–1

1

2

3

–2

–3

–4

–5

y

1 3 42–3–4 –2 –1 x0

positive

Chapter 5 ● Skills Practice 407

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13.

2

1

3

4

–1

–2

–3

–4

y

–1 1 2–5–6 –4 –3 –2 x0

14.

–2

–1

–3

1

–4

–5

–6

–7

y

–1 1 2–5–6 –4 –3 –2 x0

15.

4

5

6

7

8

3

2

1

y

1 3 42–3–4 –2 –1 x0

16.

1

2

3

4

–1

–2

–3

–4

y

1 3 42–3–4 –2 –1 x0

17.

3

4

5

6

1

2

–2

–1

y

3 5 64–1–2 1 2

x

0

18.

2

3

4

5

1

–3

–2

–1

y

2 31–4–5 –2–3 –1 x0

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Use the coordinates of the points shown to calculate the slope of each line.

19.

1

2

3

(1, 2)

(0, –2)

–1

–2

–5

–4

–3

y

3 421–3–4 –1–2 x0

20.

1

2

3

4

5

6

–2

–1

y

2 3

(1, 5)

1–4–5 –2 –1–3 x0

(–2, –1)

m � 2 � (�2)

________ 1 � 0

� 4 __ 1 � 4

21.

–3

–4

–2

–1

1

2

–6

–5

y

1–6–7 –3–4 –1–2–5 x0

(–7, 2)

(–2, –3)

22.

1

2

3

4

5

6

–2

–1

y

5–2–3 1 3 42–1 x0

(–1, 5)

(1, –1)

23.

1

2

3

–5

–1

–2

–3

–4

y

4–3–4 2 31–2 –1 x0

(4, 2)

(–4, –4)

24.

1

2

3

–5

–1

–2

–3

–4

y

–7–8 –2 –1–3–4–6 –5 x0

(0,3)

(–5,–3)

Chapter 5 ● Skills Practice 409

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25.

5

6

7

–1

3

4

2

1

y

–8–9 –3 –2 –1–4–5–7 –6

x

0

(–3, 1)

(–9, 5)

26.

5

6

7

–1

3

4

2

1

y

–1 5 6 7431 2 x0

(6, 4)

(2, 6)

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Skills Practice Skills Practice for Lesson 5.4

Name _____________________________________________ Date ________________________

Running in a MarathonSlope-Intercept Form

Vocabulary Define each term in your own words.

1. linear equation

2. y-intercept

3. slope

4. positive slope

5. negative slope

6. slope-intercept form

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Problem Set Identify the slope and y-intercept of the line shown on each graph.

1.

–2

–3

–1

1

–4

–5

–6

–7

2 4 53–3 –1–2 1

y

x0

2.

x

5

6

7

8

–1

3

210–2

2

–3

1

–4

4

–5–6

y

slope: 3; y-intercept: �5

3.

1

2

3

4

–1

–2

–3

–4

1 3 42–3–4 –2 –1

y

x0

4.

1

2

3

4

–1

–2

–3

–4

1 3 42–3–4 –2 –1

y

x0

5.

–2

–3

–1

1

–4

–5

–6

2 4 53–1 1

y

x0

2

6 7

6.

1

2

3

4

–1

–2

–3

–4

1 3 42–3–4 –2 –1

y

x0

Chapter 5 ● Skills Practice 413

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Write each equation in slope-intercept form. Then identify the slope and y-intercept for the graph of each equation.

7. 3x � y � 8 � 0 8. 6x � y � 5 � 0

y � �3x � 8

slope: �3; y-intercept: 8

9. 5x � y � �3 10. 4x � y � �1

11. 2x � 3y � 24 12. 5y � 2x � 20

13. x __ 3 �

y __

5 � 1 14. � x __

2 �

y __

3 � 1

Use the slope and y-intercept to graph each equation.

15. y � 3x � 2 16. y � 2x � 7

1

2

3

4

–1

–2

–3

–4

1 3 42–3–4 –2 –1

y

x0

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17. y � �2x � 4 18. y � �x � 6

19. y � 5 __ 3 x � 1 20. y � 3 __

2 x � 5

21. y � � 1 __ 2 x � 4 22. y � � 4 __

3 x � 2

Chapter 5 ● Skills Practice 415

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Compare the slopes and y-intercepts of each pair of equations. Use complete sentences in your answer.

23. y � x

y � 2x

The lines have the same y-intercept. The slope of the second line is 2 times the slope of the first line. Both of the slopes are positive.

24. y � �3x

y � x

25. y � 2x � 5

y � 2x � 1

26. y � �x � 2

y � �x � 4

27. 3y � x � 6

2 � y � �3x

28. 5 � x � y

2x � 10 � 2y

29. y � 2x � �1

5 � 5y � 10x

30. 2y � �6 � 2x

9 � 3x � 3y

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Skills Practice Skills Practice for Lesson 5.5

Name _____________________________________________ Date _________________________

Saving MoneyWriting Equations of Lines

Vocabulary Give two examples of each term.

1. equation of a horizontal line

2. equation of a vertical line

3. linear equation in slope-intercept form

4. linear equation in point-slope form

Problem Set Write an equation of a line in slope-intercept form that has the given criteria.

1. slope is �3 and y-intercept is 7

y � �3x � 7

2. slope is 8 and y-intercept is 2

3. slope is 4 and y-intercept is �3

4. slope is �1 and y-intercept is �8

5. slope is 2 __ 3 and y-intercept is �5

6. slope is � 1 __ 4 and y-intercept is 1

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Write an equation in point-slope form of the line that passes through the given point and has the given slope. Then write the equation in slope-intercept form.

7. Has slope of 3 and passes through (1, 2) 8. Has slope of 5 and passes through (6, 1)

( y � 2) � 3( x � 1)

y � 2 � 3x � 3

y � 3x � 3 � 2

y � 3x � 1

9. Has slope of �2 and passes through (3, 4) 10. Has slope of �5 and passes through (2, 5)

11. Has slope of 1 and passes through (3, �2) 12. Has slope of 2 and passes through (�1, 4)

13. Has slope of �3 and passes through (�3, 2) 14. Has slope of �1 and passes through (8, �5)

Chapter 5 ● Skills Practice 419

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Write an equation of the line in slope-intercept form that passes through each given set of points.

15. Passes through (2, 9) and (4, 13) 16. Passes through (3, 2) and (6, 11)

m � 13 � 9 _______ 4 � 2

� 4 __ 2 � 2

( y � 9) � 2( x � 2)

y � 9 � 2 x � 4

y � 2 x � 4 � 9

y � 2 x � 5

17. Passes through (�4, �10) and (3, �3) 18. Passes through (�1, �9) and (3, �1)

19. Passes through (2, 10) and (7, 5) 20. Passes through (1, 9) and (4, 3)

21. Passes through (�2, �1) and (2, �9) 22. Passes through (�5, �2) and (3, �10)

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Write an equation in slope-intercept form for the line shown in each graph.

23.

1

2

3

4

–1

–2

–3

–4

1 3 42–3–4 –2 –1

y

x0

24.

–2

–1

–3

1

–4

–5

–6

–7

y

–1 1 2–5–6 –4 –3 –2 x0

y-intercept: 1; slope: �3, y � �3x � 1

25.

–2

–3

–1

1

–4

–5

–6

2 4 531

y

x0

2

6 7 8

26.

1

2

3

4

–1

–2

–3

–4

1 3 42–3–4 –2 –1

y

x0

Chapter 5 ● Skills Practice 421

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27.

1

2

3

4

–1

–2

–3

–4

1 3 42–2 –1

y

x0 5 6

28.

1

2

3

4

–1

–2

–3

–4

1 3 42–2 –1

y

x0 5 6

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Skills Practice Skills Practice for Lesson 5.6

Name _____________________________________________ Date _________________________

Spending MoneyLinear and Piecewise Functions

Vocabulary Match each definition or description to its corresponding term.

1. set of output values of a function a. domain

2. function that can be written in the form y � mx � b b. range

3. function represented by different expressions in c. positive slope

different parts of its domain

4. shows decreasing y-values as the value of x increases d. negative slope

5. set of input values of a function e. linear function

6. shows increasing y-values as the value of x increases f. piecewise function

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Problem Set Write the domain and range of each function in terms of the given problem situation.

1. Gerald gets $5 plus $2 per hour for babysitting. He works 5 hours over the weekend. The

function f(x) � 2x � 5 shows the relationship between the number of hours he works over

the weekend and the amount of money he earns.

6

7

8

4

5

3

2

1

y

1 6 7 8542 3

x

0

Mon

ey E

arne

d

Time in Hours

Babysitting This Weekend

domain � {all whole numbers from 0 to 5}

range � {all whole numbers from 5 to 15}

2. Kim has a 12-page science report to write. She writes 3 pages each day. The function

f(x) � 12 � 3x shows the relationship between the number of days and the number of pages

she has left to write.

12

14

16

8

10

6

4

2

y

1 6 7 8542 3

x

0

Pag

es L

eft t

o W

rite

Number of Days

Science Report

domain �

range �

Chapter 5 ● Skills Practice 425

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3. Tim has $75 for lunch money. He spends $5 each day. The function f(x) � 75 � 5x shows

the relationship between the number of days and the amount of money he has left.

60

70

80

40

50

30

20

10

y

5 30 35 40252010 15

x

0

Mon

ey L

eft

Time in Days

Lunch Money

domain �

range �

4. Marji is on a hike. At dawn she is 10 miles from the parking lot. Marji estimates that she will

average 4 miles per hour for the next 10 hours. Then the hike will be over and Marji’s friend

will pick her up. The function f(x) � 4x � 10 shows her distance from the parking lot at any

given time.

30

40

20

10

y

30 402010 x0

Dis

tatn

ce fr

om th

e P

arki

ng L

ot (

mile

s)

Time in Hours

Birdwatching Hike

domain �

range �

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For each piecewise function shown in the graph, state the number of pieces and the domain of each piece.

5.

6

7

8

9

4

5

3

2

1

y

1 6 7 8 9542 3 x

6.

6

7

8

9

4

5

3

2

1

y

1 6 7 8 9542 3 x

3 pieces

{0 � x � 3}, {3 � x � 5}, {5 � x � 9} or

{0 � x � 3}, {3 � x � 5}, {5 � x � 9}

7.

6

7

8

9

4

5

3

2

1

y

1 6 7 8 9542 3 x

8.

6

7

8

9

4

5

3

2

1

y

1 6 7 8 9542 3 x

Chapter 5 ● Skills Practice 427

Name _____________________________________________ Date _________________________

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9.

30

35

40

45

20

25

15

10

5

y

5 30 35 40 45252010 15 x

10.

30

35

40

45

20

25

15

10

5

y

5 30 35 40 45252010 15 x

Write an equation for each piecewise function shown in the graph.

11.

6

7

8

9

4

5

3

2

1

y

1 6 7 8 9542 3 x

12.

6

7

8

9

4

5

3

2

1

y

1 6 7 8 9542 3 x

f( x) � � 2 x � 1 0 � x � 3 7 3 � x � 10

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13.

6

7

8

9

4

5

3

2

1

y

1 6 7 8 9542 3 x

14.

6

7

8

9

4

5

3

2

1

y

1 6 7 8 9542 3 x

Graph each piecewise function.

15. f(x) � � x � 1 0 � x � 5

6 5 x � 10

16. f(x) � � 4 0 � x � 4

8 � x 4 x � 10

6

7

8

9

4

5

3

2

1

y

1 6 7 8 9542 3 x

Chapter 5 ● Skills Practice 429

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17. f(x) � � 6 � x 0 � x � 3

3 3 x � 5

x � 2 5 x � 10

18. f(x) � �

6 � x 0 � x � 2

x � 2 2 x � 6

8 6 x � 10

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Skills Practice Skills Practice for Lesson 5.7

Name _____________________________________________ Date _________________________

The School PlayStandard Form of a Linear Equation

Vocabulary Give two examples of each term.

1. linear equation in slope-intercept form

2. linear equation in point-slope form

3. linear equation in standard form

Problem Set Without graphing, calculate the x- and y-intercepts of the graph of each equation.

1. 3x � y � �2

x-intercept y-intercept

3x � (0) � �2 3(0) � y � �2

x � � 2 __ 3 y � �2

2. �5x � y � 10

3. x � 2y � 8

4. x � 3y � �6

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5. 2x � 5y � 20

6. �3x � 4y � �12

7. 5x � 2y � �1

8. �7x � 3y � 2

9. 2 __ 3 x � 1 __

2 y � 18

10. 1 __ 5 x � 3 __

4 y � 12

Chapter 5 ● Skills Practice 433

Name _____________________________________________ Date _________________________

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Graph each equation.

11. 5x � 3y � 15 12. 3x � 4y � 12

1

2

3

–5

–4

–1

–2

–3

y

3 5 64–1–2 21 x0

13. �2x � 6y � 12 14. �5x � 2y � 20

15. 4x � 2y � 6 16. 15x � 30y � 45

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17. �40x � 25y � 100 18. �25x � 30y � 75

Write each equation in standard form.

19. 3y � x � 5 � 0 20. y � 2x � 3 � 0

x � 3y � 5

21. y � 2x � 4 22. y � x � 6

23. y � 2 __ 3 x � 5 24. y � 1 __

4 x � 1

25. y � 1 __ 3 x � 2 __

5 26. y � 2 __

3 x � 1 __

4

Chapter 5 ● Skills Practice 435

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Write a linear equation in standard form to model each situation.

27. You have a $25 book store gift card. You want to buy magazines that cost $3 each and

books that cost $5 each.

3x � 5y � 25

28. Ed has $35 to buy paints and brushes for a school project. Jars of paint cost $4 each. The

brushes are $2 each.

29. Gail plans to spend $20 on rides at an amusement park. Some rides cost $1 and others

cost $2.

30. A basketball team scored 60 points by making a combination of 2-point shots and 3-point shots.

Write each equation in slope-intercept form.

31. 4x � 3y � 5 32. 5x � 2y � 3

3y � �4x � 5

y � � 4 __ 3

x � 5 __ 3

33. �4x � 3y � 2 34. �6x � 5y � �4

35. 2x � 3y � �1 36. 3x � 7y � 2

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Chapter 5 ● Skills Practice 437

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Skills Practice Skills Practice for Lesson 5.8

Name _____________________________________________ Date _________________________

Earning InterestSolving Literal Equations

Vocabulary Write the term that best completes each statement.

1. The equation I � Prt is a(n) formula.

2. is the initial amount of money borrowed or invested.

3. In the formula I � Prt, the value for r is the .

4. When the interest rate is a fixed percent, invested money earns .

5. A(n) often has more than two different variables.

6. is the amount earned when saving or investing money.

Problem Set Solve each equation for the given variable.

1. I � Pr t for r 2. I � Pr t for t

r � I ___ Pt

3. A � l � w for l 4. A � l � w for w

5. P � 2(l � w) for l 6. P � 2(l � w) for w

7. D � r t for r 8. D � r t for r

9. A � 1 __ 2 bh for b 10. A � 1 __

2 bh for h

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Use the given information to determine the amount of interest earned.

11. Jennifer deposits $800 in an account that earns 5% interest for 1 year.

I � 800 � 0.05 � 1

I � $40

12. Tonya deposits $1200 in an account that earns 3% interest for 1 year.

13. David deposits $1400 in an account that earns 2% interest for 3 years.

14. Lin deposits $3500 in an account that earns 6% interest for 5 years.

15. Shania deposits $3200 in an account that earns 4.5% interest for 7 years.

16. Horace deposits $6800 in an account that earns 6.7% interest for 4 years.

17. Leslie deposits $7500 in an account that earns 3.2% interest for 6 months.

18. Tabitha deposits $4000 in an account that earns 4.8% interest for 9 months.

19. Sean deposits $12,500 in an account that earns 5.5% interest for 3.5 years.

20. Jorge deposits $18,800 in an account that earns 3.6% interest for 6.25 years.

Chapter 5 ● Skills Practice 439

Name _____________________________________________ Date _________________________

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Use the given information to solve each problem. Round your answers to two decimal places.

21. Calculate the amount of time it will take to earn $200 in simple interest if you deposit $8000

into an account that earns 3% interest.

t � I ___ Pr

� 200 ___________ 8000 � 0.03

� 5 __ 6 � 0.83 years

22. Calculate the amount of time it will take to earn $150 in simple interest if you deposit $9000

into an account that earns 5% interest.

23. Calculate the amount of time it will take to earn $500 in simple interest if you deposit $6000

into an account that earns 7.5% interest.

24. Calculate the amount of time it will take to earn $3500 in simple interest if you deposit

$10,000 into an account that earns 6.5% interest.

Use the given information to answer each question.

25. How far can a car travel in 4.5 hours at an average speed of 45 miles per hour?

D � r t � 4.5 � 45 � 202.5 miles

26. How far can a car travel in 1.5 hours at an average speed of 35 miles per hour?

27. How long does it take to run 10 miles at an average speed of 8 miles per hour?

28. How long does it take to walk 6 miles at an average speed of 4 miles per hour?

29. A car travels 350 miles in 6.5 hours. What is the average speed?

30. A car travels 150 miles in 3.25 hours. What is the average speed?

440 Chapter 5 ● Skills Practice

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Use the following area formulas to answer the questions.

rectangle parallelogram triangle

A � l � w A � bh A � 1 __ 2 bh

31. Mike bought enough grass seed to plant 500 square yards. If his rectangular lawn is

20 yards wide, how long can it be?

l � A __ w � 500 ____ 20

� 25 yards

32. Shari has enough yarn to knit a rectangular scarf that is 360 square inches. If she makes the

scarf 8 inches wide, how long will it be?

33. A parallelogram with a base of 3.5 centimeters has an area of 6.3 square centimeters. What

is the height?

34. A parallelogram with a base of 15.5 centimeters has an area of 161.2 square centimeters.

What is the height?

35. A triangle with an area of 60 square inches has a height of 15 inches. What is the base?

36. A triangle with an area of 130 square inches has a base of 13 inches. What is the height?