The question I have is trying to solve the final velocity in an energy equation that goes like this: 0.5mv^2=0.5mv^2+mgy (The final velocity being on the LS). I'm not given the mass of the skier going down the hill so I divide to cancel the mass out. I then rearrange to get Vf^2 = V^2+gy. I've pretty much nailed it down to a simple algebra problem but I can't see what's wrong! Oh, I might add that I always plug numbers in before rearranging equations but my teacher doesn't like me doing that.