Therefor the expression inside the absolute value bars can equal either 3 or -3, so you need to set up two separate expresstions representing that fact.


Expression 1

Add 13 to both sides

Divide by 6

reduce



Expression 2

Add 13 to both sides

Divide by 6

reduce

So either answer will work, if you plug in the Expression 1, you will get
|3| which is 3, if you plug in Expression 2, you will get |-3| which is ALSO 3