Which of the following sets of numbers could represent the side lengths of a right triangle?

(a) 5, 8, 12

(b) 5, 9,12

(c) 5, 10, 13

(d) 5, 12, 13

If it is a right triangle, then those 3 numbers have to satisfy this equation:

longest side ^2 (or) hypotenuse ^2 = side1 ^2 + side2 ^2

Only (d) 5, 12, 13 meets this requirement.