Answer :

AyaZ
[tex]1^{2} + 8^{2} =1+64=65[/tex]
Im thinking there are two ways....
8² +1² = 8 * 8 + 1 *1 = 64 + 1 = 65      
7² + 4² = 7 * 7 + 4 * 4 = 49 + 16 = 65