For 5, you need to get y by itself. So subtract 6 from each side. You get 36=-2d. You also need d positive. So divide each side by -2. You get -18=d. So the answer is d=-18.
For 6, you need to get y by itself. So subtract 31 from each side. You get 15y=30. Divide by each side by 15 to get y=2. The answer is y=2.
I hope this helps! :)
