Summer holiday problem

[Pam]

Can anyone explain why Pythagorean Triples can be found from the formula

2mn, n-m, m+n where m and n are integers and n>m

[Evan]

well, let's take it as follows.
Always we have (n -m) +(2mn)=n-2m n +m+4m n =n +2m n +m=(m +n ) .
So that's it.