G.6.4.1 Going the Distance

Andre says, “I know that I can find the distance between two points in the plane by drawing in a right triangle and using the Pythagorean Theorem. But I’m not sure how to find the lengths of the legs of the triangle when I can’t just count the squares on the graph.” Explain to Andre how he can find the lengths of the legs in the triangle in the image. Then, calculate the distance between points P and Q.