1. The problem statement, all variables and given/known data A train having a velocity of x m/s is caught by a train accelerating from zero 20 seconds after the second train starts. At what time were their velocities equal? 2. Relevant equations 3. The attempt at a solution I was thinking that you'd have to assume that the train with x velocity is traveling with constant velocity and that the second train starts at t=t-20 s. However, I'm confused as to how I would find when their velocities would be equal.