Acceleration problem At the instant the traffic light turns green, an automobile starts with a constant acceleration a of 2.3 m/s$^2$. At the same instant a truck, traveling with a constant speed of 9.8 m/s, overtakes...--prophetes.ai

Acceleration problem At the instant the traffic light turns green, an automobile starts with a constant acceleration a of 2.3 m/s$^2$. At the same instant a truck, traveling with a constant speed of 9.8 m/s, overtakes and passes the automobile. (a) How far beyond the traffic signal will the automobile overtake the truck? (b) How fast will the car be traveling at that instant? I have 83.51 for a, which is right. I'm not sure how to solve b. I have v = at, then v = 2.3 83.51. It's not accepting that, though.

$$v_0t+\frac12at^2=Vt$$

$$t(1.15t-9.8)=0$$

$$t=196/23$$

$$v=v_0+at=2.3*\frac{196}{23}=19.60(m/s)$$