Name
Date
Class
Reteach
LESSON
3-3 Solving Inequalities by Multiplying or Dividing
The inequality sign must be reversed when multiplying by a negative number.
Multiplying by a negative number:
Multiplying by a positive number:
25
?
3235
?
6 15 ✓
25
True
3 2 3 5
Multiply both sides
by a positive
number.
Multiply both
sides by a
negative number.
?
Statement is true.
6 15 ✗
Statement is
false.
6 15 ✓
Reverse
inequality sign so
statement is true.
x ⱖ 1 and graph the solutions.
Solve ___
⫺4
x ⬎ ⫺2 and graph the solution.
Solve __
3
x 1
___
x 2
__
4
3
x 3 2 3 __
3
True
?
x 4 1
4 ___
Multiply both sides by 3.
Multiply both
sides by 4.
4
x 6
Reverse
inequality sign.
x 4
Solve each inequality and graph the solutions.
3 g 3
x 2
2. __
1. __
3
4
Solve each inequality.
v
3. 1 ___
5
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
a107c03-3_rt.indd 22
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4. __
6
22
Holt Algebra 1
6/5/06 6:27:55 PM
Name
Date
LESSON
3-3
Class
Reteach
Solving Inequalities by Multiplying or Dividing
(continued)
The inequality sign must also be reversed when dividing by a negative
number. Dividing by a negative number:
86
True
6
8 ___
___
2
Divide both sides by a negative number.
2
?
4 3
Statement is false.
4 3
Reverse inequality sign so statement is true.
Solve 2m 10 and graph the solutions.
Solve 3x 12 and graph the solution.
2m 10
3x 12
3x ____
12
___
3
x 4
10
2m ___
_____
Divide both
sides by 3.
3
2
Dividing by a positive.
Do not reverse inequality sign.
Divide both
sides by –2.
2
m 5
Dividing by a negative.
Reverse inequality sign.
Solve each inequality and graph the solutions.
5. 5q 10
6. 4x 16
q2
x 4
Solve each inequality.
7. x 5
8. 30 10d
x 5
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
a107c03-3_rt.indd 23
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