Conservation of Linear Momentum

[affordable]

Homework Statement

There is a ball that's going 45 m/sec and it's hitting the ground at an 80 degree angle, but when it bounces off, it has a 58 degree angle. The coefficient of restitution is not known.

Homework Equations

The Attempt at a Solution

I'm just wondering, but is the x-component of the velocity the same before the collision as afterwards if the x-axis is the ground?

 

[da_nang]

With negligible air resistance, I'd say yes.