Question

Which side lengths form a right triangle?
(Look in the picture for the answers)

Answer 1

Pythagoras' Theorem only works with right angle triangles.

A makes a right angles triangle because:
√3² + 4² = 5

However B doesn't because:
√7² + 8² = 10.631 (which is not 9)

Nor does C because:
√3² + 9² = √90 (which is not √95)

So the answer is A