I got this picture from photomath, hope it helps
Answer:
What to prove, solve for?
The answer is D
Hope this helps
The answer is A hope this helped c: if you'd need an explination id be happy to give you one
A^2 + b^2 = c^2
where a and b are the sides, and C is the hypotenuse (longest side)
basically
a + 13^2 = 16^2
so
a + 169 = 256
to find what A is, 256 - 169 = a = 87
but, because a is squared, you need the square root of 87 if it is a whole number, but it isn't-
Answer =