The equation given in the question is not written properly. I am answering the question based on my thinking of the equation given in the question.
s = 2rh Then r = s/2h
I hope that this is the answer that you were looking for and the answer has actually come to your desired help. It you have any doubts, you can always ask for clarifications.
So you didn't put an actual question. To find the money he makes you just plug in the numbers. If he works 4 shifts at the theater you replace x with 4. Then, you find 85 x 4. You do the same thing with 15y.
