Hey there!
You got the first part right where you added r to both sides. However, you need to make sure that you complete all actions on both sides, including canceling out parts of terms by division. The only thing you need to do is divide both sides by h instead of just the left. This will make your answer:
[tex]y = \frac{b+r}{h} [/tex]
Hope this helped you out! :-)
