Think your triangle is a right triangle? Want to be sure? If you have the length of each side, apply the Pythagorean theorem to the triangle. If you get a true statement when you simplify, then you do indeed have a right triangle! If you get a false statement, then you can be sure that your triangle is not a right triangle. Check out this tutorial and learn how use the Pythagorean theorem to see if a triangle is a right triangle!