My lecturer was asked me to prove that V_{0}= Sqrt(V_{i}^{2}-2Gs)
Few more hours then I have to hand in my answer~ who can help me
my advice is: the next time you take a class, pay attention, and ask for help before the last minute. You want your teacher to give you credit for doing something you don't even understand, and you want us to help you in your deceit. I won't, and I don't think anyone else should, but I can hardly stop them.
I am going to make some assumptions here, but the others have given good advice about this.
I'm going to assume you are starting a Summer Physics program of some kind, so your equation would be one involving Kinematics rather than Work-Energy.
I'll go so far as to give you the two pertinent equations:
$\displaystyle s = \frac{1}{2} (v_0 + v)t$
$\displaystyle v = v_0 + at$
As this appears to be part of an assignment that is for a grade let's see what you can do with these.
-Dan