Converse of Pythagorean Thm

If the square of one side of a triangle is equal to the sum of the squares of the other two sides, then the triangle is a right triangle.

Some Pythagorean Triples…

3,4,5 (or 6,8,10 or 9,12,15 or 12,16,20, or 15, 20, 25)

5,12,13 (or 10, 24, 26) 8,15,17 7,24,25

Other options…

If c^2<a^2+b^2, then m<C is less than 90… and

triangle is ACUTE

If c^2>a^2+b^2, then m<C is greater than 90… and

triangle is OBTUSE