15-6<x<15+6

The inequality \( 15 - 6 < x < 15 + 6 \) can be simplified as follows:

1. Calculate \( 15 - 6 \): \[ 15 - 6 = 9 \]

2. Calculate \( 15 + 6 \): \[ 15 + 6 = 21 \]

So the inequality can be rewritten as: \[ 9 < x < 21 \]

This means that \( x \) must be greater than 9 and less than 21. Therefore, the solution set for \( x \) is \( (9, 21) \).