10.21 Physics! Help Please!?

Question

A 1200 kg car is approaching the hill shown in the figure at 14.0 m/s when it suddenly runs out of gas.

http://session.masteringphysics.com/problemAsset/1011893/9/1011893.jpg

What is the car's speed after coasting down the other side?

Answer 1

mg(∆h)=1/2m(∆v)^2

g(∆h)=1/2(∆v)^2

10x5=(1/2)x(∆v)^2

∆v=10

v in other side=24