q + 13 = 120

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8

I'm going to assume your problem is this:
(q/8) + 13 = 120

If so, start by subtracting 13 from both sides of the equation. Whatever operation you do to one side of an equation you must do to the other side as well. Next, multiply both sides by 8. Once you do that operation, you will be finished. To check, substitute the value you found for q back into the original equation. It always helps to check your work!

I hope this will help.