Here's the problem: A motor car A is at rest at a traffic light. as the light turns green A starts to accelerate and at the same moment a motorbike M moves past A with a constant velocity of 15m.s^-1. Thats the Velocity Time graph, the values on the left and bottom are 15 and 10 respectively. The question is, after how many seconds will car A catch Bike M. I figured the acceleration of M=0 and A=1.5. and to work out the time I should use v*t=(v*t)/2. But then I get stuck... Help appreciated, thanks!