2.6 Set Operations and Compound
Inequalities
Solving a Compound Inequality
Step 1 Solve each inequality in the compound inequality
individually.
Step 2 If the inequalities are joined with and, then the
solution set is the intersection of the two individ-
ual solution sets.
If the inequalities are joined with or, then the
solution set is the union of the two individual
solution sets.
Solve and
The solution set is
Solve or
The solution set is
–1 012345
1 - q, 0 4 ́ 3 4, q 2.
xÚ 4 x...0.
–1 0 1 2 3
1 1, 3 2.
x 71 and x 63
x+ 172 and 2 x 66
x+ 172 2 x 6 6.
CONCEPTS EXAMPLES
126 CHAPTER 2 Linear Equations, Inequalities, and Applications
2.7 Absolute Value Equations and
Inequalities
Solving Absolute Value Equations and Inequalities
Let kbe a positive number.
To solve solve the following compound
equation.
To solve solve the following compound
inequality.
axb>k or axb<k
axb>k,
axbk or axbk
axbk,
Solve
Add 7.
The solution set is.
Solve
Add 7.
The solution set is
082 46 10
1 - q, 4 2 ́ 1 10, q 2.
x 710 or x 64
x- 773 or x- 7 6- 3
|x- 7 | 7 3.
082 46 10
5 4, 10 6
x= 10 or x= 4
x- 7 = 3 or x- 7 =- 3
|x- 7 |=3.
To solve solve the following compound
inequality.
To solve an absolute value equation of the form
solve the following compound equation.
axbcxd or axb 1 cxd 2
axbcxd,
k<axb<k
axb<k, Solve
Add 7.
The solution set is
Solve
The solution set is E^43 , 8F.
x=
4
3
3 x= 4
x= 8 x+ 2 =- 2 x+ 6
x+ 2 = 2 x- 6 or x+ 2 =- 12 x- 62
|x+ 2 |=| 2 x- 6 |.
0821046
1 4, 10 2.
4 6 x 610
- 36 x- 763
|x- 7 | 6 3.