Write the Correct Answer s2

Name Date Class

Problem Solving

Variables and Expressions

Write the correct answer.

Holt McDougal Coordinate Algebra

Name Date Class

1. For her book club, Sharon reads for 45 minutes each day. Write an expression for the number of hours she reads in
d days.

3. According to the 2000 census, the number of people per square mile in Florida was about 216 more than the number of people per square mile in Texas. Write an expression for the number of people per square mile in Florida if there were t people per
square mile in Texas.

2. The minimum wage in 2003 was $5.15. This was w more than the minimum
wage in 1996. Write an expression for
the minimum wage in 1996.

4. The cost of a party is $550. The price
per person depends on how many
people attend the party. Write an expression for the price per person if p people attend the party. Then find the price per person if 25, 50, and 55
people attend the party.

Holt McDougal Coordinate Algebra

Name Date Class

Use the table below to answer questions 5–6, which shows the years five states entered the Union. Select the best answer.

5. North Carolina entered the Union x years
after Pennsylvania. Which expression shows
the year North Carolina entered the Union?

A 1845 + x C 1787 + x

B 1845 - x D 1787 - x

6. The expression f - 26 represents the year
Alabama entered the Union, where f is the
year Florida entered. In which year did
Alabama enter the Union?

F 1819 H 1837

G 1826 J 1871

7. The number of states that entered the Union
in 1889 was half the number of states s that
entered in 1788. Which expression shows
the number of states that entered the Union
in 1889?

A 2s C s + 2

B s ¸ 2 D 2 - s

Holt McDougal Coordinate Algebra

Name Date Class

4. Possible answer: It depends on the number of minutes used. Plan A is cheaper if you use less than 300 minutes each month. Plan B is cheaper if you use more than 300 minutes each month. If you use exactly 300 minutes each month, the plans cost the same.

Problem Solving

1. 45d 2. 5.15 - w

3. 216 + t

4. ; $22, $11, $10

5. C 6. F

7. B

Reading Strategies

1. Possible answers: 10y, 10 • y, and 10(y)

2. Possible answers: k divided by 6, the quotient of k and 6

3. b - 4 4. 4 - b

5. 20m 6. 58 + t

Solving Equations by
Adding or Subtracting

Practice A

1. m = 7 2. t = 23

3. p = 4 4. a = 8

5. c = 5 6. y =

7. b = 0 8. w = 9

9. p = 4 10. x = 4

11. x = -2 12. r = 14.4

13. x + 18 = 86; 68; The score on the second test was higher than the first, so the score on the first test should be less than 86.

14. x - 4 = 29; 33˚F; The actual temperature was lower than predicted, so the predicted temperature should be greater than 29˚F.

15. x + 72 = 122; $50; The amount of money raised in one week should be less than the two-week total of $122.

Practice B

1. g = 22 2. t = 2

3. m = 20 4. x = 5.7

5. n = 6. p = 1

7. k = 38 8. w = -2.3

9. r = -4 10. y = 17

11. b = -2 12. a = 0

13. x + 0.75 = 12.25; $11.50; Marietta received a raise, so her previous wage should be less than $12.25.

14. x + 4 = 56; 52in.; Brad’s height increased, so his previous height should be less than 56 inches.

15. x - 2.6 = 58.4; 61 s; Heather’s race time was less than her practice time, so her practice time should be greater than
58.4 s.

16. x + 2981.1 = 6378.1; 3397 km; Earth is larger than Mars, so the radius of Mars should be less than 6378.1 km.

Practice C

1. d = 21 2. f = -1.3

3. n = 1 4. x = 13

5. h = - 6. y = -17

7. x + 12 = 27; x = 15

8. x - 7 = 3; x = 10 9. x - 6 = -2; x = 4

10. x + 4.7 = 8.1; x = 3.4

11. x + 2 = 7; 4in.; The plant grew, so the previous height should be less than 7 inches.

12. x - 36.8 = 475.2; 512 MB; The new software used some of the available memory, so the amount of memory before the new software should be more than 475.2 MB.

13. x - 0.43 = 28.3; 28.73 s; The time was faster in 2004 than 2002, so the 2002 time should be slower than 28.3 s.

Holt McDougal Coordinate Algebra