1. The problem statement, all variables and given/known data let m|d, n|d and gcd(m,n) = 1. show mn|d 2. Relevant equations gcd(m,n) = d = mx + ny for x and y in integers 3. The attempt at a solution d = mr d = ns 1 = mx + ny 1 = (d/r)x + (d/s)y I don't know, a bit lost, just moving stuff around and not making any real progress. Any tips?