Answer:
144 or 72^2
Explanation:
You have one leg a 5 and the other leg we don't know, well we know the hyponuse is a 13.
So the first step is
A^2 + B^2 = C^2
2 step,
5^2 + B^2 = 13^2
3 step
5 x 5 = 25 and 13 x 13 = 169
25 + B^2 = 169
4 step
169 - 25 = 144
144 divided by 2 is 72, so 72 x 72 is 144.
If you have an answer 72 squared or 144 both will work.
It does not help that you don't give the answers.