Homework Statement
Let r,s,t and v be integers with r>0. If st=r+v and gcd(s,t)=r, then gcd(v,t)=r
Homework Equations
Just stumped. I am not sure what to do next.The Attempt at a Solution
There are 2 integers d and e such that S=dR and T=eR, and 2 integers a and b such that Sa+Tb=R. I know I...