Solving tricky triangle problems

Grade 9s are working on solving some challenging problems.

We are asked to prove whether triangle PQR is a right triangle or not.

We looked at calculating missing sides with the pythagorean theorem.

Some of us were thrown off by the potential hypotenuse being the base of the triangle, or by the fact that we were having to prove something instead of solving something.

We needed to use the pythagorean theorem again to show that 10^2+8.2^2=11^2 was not true, so it is not a right angle triangle.

The pythagorean theorem is only true for right triangles, so if the pythagorean theorem doesn’t work, we can assume the triangle is not a right triangle.