Which set of side lengths forms a right triangle?

2, 3,13
4, 6, 10
9, 12, 18
15, 36, 39

2, 3, 13

Explanation: You take a^2+b^2=c^2 and substitute the side lengths and solve until you find one where a^2+b^2 actually equals c^2 and that’s your answer

15, 36, 39
step by step: use pythagorean theorem: a^2+b^2=c^2
2^2+3^2=13^2
4+9 does not equal 169 so it’s not 2,3,13
4^2+6^2=10^2
16+36 does not equal 100 so it’s not 4,6,10
9^2+12^2=18^2
81+144 does not equal 324
15^2+36^2=39^2
1521=1521 so that’s the answer :)
also 15 36 39 is a pythagorean triple which means it forms a right angle

The answer to that is 6