1. Tentukan nilai x? a. | ×- 20| =23? b. | -2× | + 5 = 13?

a•
|x - 20| = 23
⏺ x - 20 = 23 --> x = 43
⏺ x - 20 = -23 --> x = -3

b•
|-2x| + 5 = 13
|-2x| = 13 - 5
⏺ -2x = 6 --> x = -3
⏺ -2x = -6 --> x = 3

a. x- 20= 23
x = 23 + 20
x = 43

b. -2x + 5 = 13
-2x = 13 - 5
-2x = 8
x = 8 : -2
x = -4