Pythagorean Theorem and identify right triangles.

In triangle PQR, the sides PQ, QR and PR measure 15 in, 20 in and 25 in. respectively. Prove that PQR is a right triangle.

Which number is located at point a on the number line? a number line is shown from negative 10 to 10 with each interval mark on the number line representing one unit. point a is labeled one interval mark to the right of negative 5.