Hi!

I was wandering if anyone of you could help me solve the following equation:

$\displaystyle 2^x + 5^y = k^2$

where $\displaystyle x, y, k$ are integers.

I know the best way to solve it is to use modulo but, to be honest, I don't really know how modulo works in such equations.

Maybe you have another approach to this task - please share it