Vf=Vo+at

DX=Vo(t)+at²/2

Vf²=Vo²+2aDX

These equations are found in any physics text.  Practice your algebra and isolate the different variables in these equations.

Remember, if an object is starting from rest (zero m/s) then Vo=0 and if an object comes to rest, then Vf=0
Click here, login, and solve:"stopping distance" and "acceleration".

Below is a derivation of the third equation above.  I show this to all classes just to let students know how we can insert things and juggle them around to arrive at new equations.  We will do this often.  The good news is that you are not required to know all these steps, just how to use the resulting equations.  If you have a greater interest in doing this sort of thing, knock yourself out!
 

Xf-Xo=Vt, where v=average velocity, or Vavg
Vavg=(Vf+Vo)/2  because to average is to sum and divide by # total
if we insert second equation into first one,
we get Xf-Xo=((Vf+Vo)t)/2
introduce 2nd equation (from above)Vf=Vo+at
insert this into third equation above,	get Xf-Xo=((Vo+at+Vo)t)/2
	clean it up a bit
	get, Xf-Xo=(2Vot+at²)/2
	which is the same as 2Vot/2 + at²/2
	so we cancel out a couple of 2's,
	and get Xf-Xo=Vot+at²/2
	quite often we are asked for some final position, so physics books usually write the equation as
	Xf=Xo+Vot+at²/2