# Math Help - Integer Proof

1. ## Integer Proof

I need help with the following proof

Prove: If each of m and n is an integer, then m+n and m-n are both even if m and n are both even or both odd.

2. Originally Posted by noles2188
I need help with the following proof

Prove: If each of m and n is an integer, then m+n and m-n are both even if m and n are both even or both odd.
hint: even - write as $m=2k$, $n=2l$ [ $k,l \in \mathbb{Z}$], then finish.

odd - write as $m=2k+1$, $n=2l+1$ [ $k,l \in \mathbb{Z}$], then finish.