Originally Posted by **davie08** okay but the second part I dont understand how it got to that point from
d=(v1+v2)/2 (t)
to
v1=2d/t-v2 |

d = (v1 + v2)/2 (t)

You want to isolate the v1. Start with dividing both sides by t:

d/t = (v1 + v2)/2

Multiply both sides by 2:

2d/t = v1 + v2

Now subtract v2 from both sides:

2d/t - v2 = v1

-Dan