Question

Please help I literally don't understand-

Answer 1

Well, QR is the hypotenuse of the triangle and PT is another side of the triangle. You can use phythagoras theorem to work this out. So squareroot 13-8. That should give your your answer

Answer 2

You could find QT by using the Pythagorean Theorem.

8^2+QT^2=13^2

64+QT^2=169

QT^2=105

QT=

`√(105)`