1-D Example Modified
In this case, we still have a collision, so we have the same equations. But in this case, we know Elost = 0, and v1i = 324 m/s. We do not know v1f and v2f. Thus we still have two equations and need to solve them for two unknowns!
Here, however, both unknowns are in both equations. We need to solve them simultaneously.