Question 183359
Let one number be x. Then the other one is (x+1)

{{{(x+1)^2 - x^2}}}
{{{x^2 + 2x + 1 - x^2}}}
{{{2x + 1}}}

2x will always be even. So 2x+1 is always odd

4 , 5
25-16 = 9 which is odd