Verified answer

|x| =   x, x≥ 0

        -x, x < 0

||x+1|-4|=3

1. |x+1|-4=3

|x + 1| = 7

1a   x + 1 = 7   x = 6

1b   x + 1 = -7  x = -8

2. |x+1|-4=-3

|x + 1| = 1

2a  x + 1 = 1   x = 0

2b  x + 1 = -1  x = -2

ответ x = {-8, -2, 0, 6}