A 69kg skateboarder, at rest on a frictionless surface, throws a 4.0kg rock with the velocity given by x=3m/s y=4m/s, where the x and y axes are both in the horizontal plane. What is the x component of the subsequent velocity of the skateboarder? WHat is the y component of th subsequent velocity of the skateboarder?
Do I use the pythagorean theorem?