Answer:
c. 7
Explanation:
Let x represent the length of the missing side. The Pythagorean theorem tells you ...
x^2 + 24^2 = 25^2
x^2 + 576 = 625 . . simplify
x^2 = 49 . . . . . . . . . subtract 576
x = 7 . . . . . . . . . . . . take the square root
The length of the missing side is 7.