Question

Find two positive integers which are such that if their product is taken from the sum of their squares the difference is a perfect square.

• A. $8,5$
• B. $7,4$
• C. $6,3$
• D. $6,4$

Answer 1

The correct option is A $8,5$

Let $m,n$ be two integers

Given $m^2+n^2-mn$ is a perfect square

Let we take option "A" ; $m=8$ and $n=5$

$\Rightarrow 8^2+5^2-40=49$ is a perfect square