1. I was given the equation: (Va1-Vb1)=-(Vb2-Va1) I am suppose to prove this equation with algrebra as to why this is true. I can only use algebra, and can't use any numbers. This is an equation for elastic collisions. There is an object;A and an Object;B. My teacher said the problem would take a page or more of algrebra to prove it. Anyone have any idea how to start the problem? Any help is appricated. 2. Relevant equations We did a lab when we were given this problem, and the lab included the formula for kinetic energy. The lab showed in elastic collisions, momentum and Kinetic energy is conserved. 3. I honestly have no idea where to start.