Name
Date
Class
Practice B
LESSON
2-1
Solving Equations by Adding or Subtracting
Solve each equation. Check your answers.
1. g 7 15
2. t 4 6
g ⫽ 22
t⫽2
3 __
1
5. n __
8
8
4. x 3.4 9.1
x ⫽ 5.7
7. 6 k 32
1
n ⫽ __
2
8. 7 w 9.3
k ⫽ 38
w ⫽ ⫺2.3
10. y 57 40
11. 5.1 b 7.1
y ⫽ 17
b ⫽ ⫺2
3. 13 m 7
m ⫽ 20
1 __
2
6. p __
3
3
p⫽1
9. 8 r 12
r ⫽ ⫺4
12. a 15 15
a⫽0
13. Marietta was given a raise of $0.75 an hour, which brought her hourly wage to
$12.25. Write and solve an equation to determine Marietta’s hourly wage before
her raise. Show that your answer is reasonable.
x ⫹ 0.75 ⫽ 12.25; $11.50; Marietta received a raise, so her previous
wage should be less than $12.25.
7 inches tall. Write and solve an
1 inches this year and is now 56__
14. Brad grew 4__
4
8
equation to find Brad’s height at the start of the year. Show that your answer
is reasonable.
5 in.; Brad’s height increased, so his
1 ⫽ 56__
7; 52__
x ⫹ 4__
4
8
8
7 inches.
previous height should be less than 56__
8
15. Heather finished a race in 58.4 seconds, which was 2.6 seconds less than
her practice time. Write and solve an equation to find Heather’s practice time.
Show that your answer is reasonable.
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. The radius of Earth is 6378.1 km, which is 2981.1 km longer than the radius of
Mars. Write and solve an equation to determine the radius of Mars. Show that
your answer is reasonable.
x ⫹ 2981.1 ⫽ 6378.1; 3397 km; Earth is larger than Mars, so the radius
of Mars should be less than 6378.1 km.
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
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