A car traveling at 16.0 m/s runs out of gas while traveling up a 21.0 degree slope. How far up the hill will it coast before starting to roll back down? I tried 1/2mv^2=mgh 1/2(16)^2=9.8h 13.06=h can any one confirm if this is correct or not. I;m not sure if I have to use trig to solve this or not. help please.