Determine whether a Triangle with side lengths of 9, 12 and 15 is a Right Triangle

A Right Triangle must satisfy the Converse of the Pythagorean Theorem: a² + b² = c²
From the given side lengths, let a = 9, b = 12, c = 15  (c cannot be less than a or b)
a² + b² = (9)² + (12)²
a² + b² = 81 + 144 = 225
c² = (15)² = 225
a² + b² = c²  (225 = 225)
Therefore, a Triangle with side lengths of 9, 12 and 15 is a Right Triangle
Note: Since the side lengths are positive integers, they are a Pythagorean Triple