## Elementary and Intermediate Algebra: Concepts & Applications (6th Edition)

One way to use the distance formula to see if the points are the vertices of a right triangle is to first find the length between points using the distance formula. Then, plugging in the greatest length for $c$ and the other two for $a$ and $b$, see if the Pythagorean theorem results in a true statement. If it does not, then it is not a right triangle.