1. 3.8 Solving Equations Involving Absolute Value
Goal: Solve equations involving absolute value.

2. An equation can have more than one solution
Absolute Value
Remember:
An equation can have more than one solution
Goals for today:
Solve equations involving absolute value.
|x| - 7 = 9
x - 7 = 9 +7 +7
x = 16
Is there any other value for “x” that makes the equation true?
x = -16

3. Solve for “y”: |y| = 8

4. To solve equations involving absolute value.
Solve for |x| using the usual steps.
3|x| - 5 = 10
3IxI =15
IxI = 5
Write your solution as the positive number and its opposite.
x= -5 and 5

5. |m| - 7 = 9 +7 +7
|m| = 16
m = ±16

6. |x| + 4 = 9 -4 -4
|x| = 5
x = 5
or x = -5

7. Solve for y: 2 |y| + 1 = 15
- 1
2|y| = 14 2
|y| = 7
y = 7 or y = - 7

8. Solve for y: 3|y| - 5 = 1
y = 2 or y = - 2

9. Solve for y: |-8| + |y| = |-21| + |2|

10. Solve for y:
y = 70 or y = - 70

11. Solve for y:

12. Solve for y: |y| = -7
No Solution

13. Solve for y: -3|y| + 4 = -11

14. Solve for y: -5|y| + 8 = 18
No Solution

15. Assignment: page 146 8 – 48 even

16. 13 – 22 is mental math.
Show each step.