Pythagorean Theorem Extended
By now you know that if the square on one side of a triangle is equal to the sum of the squares on the other two sides, then the angle opposite the one side is a right angle.
1) What can you say about the angle if the side opposite is less than the sum of the squares of the other sides?
2) What can you say about the angle if the side opposite is greater than the sum of the squares of the other sides?