Constant Acceleration Question?

Question

A car moving with constant acceleration covers the distance b/w 2 points 60m apart in 6 seconds. Its velocity as it passes the second point is 15m/s. What is the velocity at the first point? What is the acceleration?

Answer 1

t=6s

d=60m

v2=15m/s

d=t*(v1+v2)/2

v1= (2d/t)-v2

= 2(60m)/(6s)-15m/s

= 5m/s

v2=v1+at

a=(v2-v1)/t

=(15m/s-5m/s)/6s

=1.67m/s^2