Exercise 22 Page 430

We are given the lengths of the three sides of a triangle, and want to determine whether the sides form a right triangle. We will need to use the Converse of the Pythagorean Theorem.

This tells us that we can use the Pythagorean Theorem in reverse to test if a triangle is right. In general, the hypotenuse c has the greatest value. Let's substitute a=20, b=48, and c=52 into a^2+b^2=c^2, and see if they produce a true statement.

The values produce a true statement, so the described triangle is a right triangle.