Download Reteach 2-8 - Humble ISD

Name
Date
Class
Reteach
LESSON
2-8
Solving Absolute-Value Equations and Inequalities
To solve compound inequalities, solve both inequalities. Then graph.
Solve x  6  4 or 2x  8.
x64
OR
2x  8
x  2
OR
x4
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Solve x  2  1
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This inequality uses OR. Its graph has
two parts.
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and
3x  12.
x21
AND
3x  12
x3
AND
x  4
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Reverse the inequality when
dividing by a negative number.
This inequality uses AND. Its
graph has one part.
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Solve and graph each compound inequality.
1x  1
1. x  3  2 or __
2
x
OR x 
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x
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Copyright © by Holt, Rinehart and Winston.
All rights reserved.
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1 x  1
1x  2  0 or 2  __
6. __
2
2
5. 3x  12 and 3x  12
a207c02-8_rt.indd 62
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4. 3x  6 and x  2  5
OR
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AND x 
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3. x  4  7 or 4x  4
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2. 6x  18 and x  6  6
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62
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Holt Algebra 2
12/7/05 6:27:14 PM
Name
Date
LESSON
2-8
Class
Reteach
Solving Absolute-Value Equations and Inequalities
(continued)
Solving absolute-value inequalities is like solving compound inequalities.
Solve: x 2
Solution: 2 x 2
Solve: x 2
Solution: 2 x 2
Solve: x 2
Solution: x 2 OR x 2
Solve: x 2
Solution: x 2 OR x 2
Solve x 2 3.
Use the solutions from the table to write
the inequalities
3 x 2 3
3 2 x 2 2 3 2
Add 2.
1 x 5
Remember:
x x if x 0
Simplify.
Solve 2x 1 5.
2x 1 5
OR 2x 1 5
2x 6
OR 2x 4
Add 1.
OR x 2
Divide by 2.
x3
Solve and graph.
7. x 3 2
8.
⫺2
x3
⫺5
x
2
2x 1 3
⫺1
2x x
Copyright © by Holt, Rinehart and Winston.
All rights reserved.
a207c02-8_rt.indd 63
3
2x 1 2
1
OR 2x OR x 63
OR 2x 1 ⫺3
⫺4
⫺2
Holt Algebra 2
4/28/06 5:31:58 PM
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Holt Algebra 2
6/9/06 12:37:52 PM