Sam wants to install a zip line across a ravine. One side is of the ravine is 45 feet tall while the other side is 65 feet. If the ravine is 21 feet wide how long must the zip line be?
The difference of the heights is 65-45=20 feet, and the length of the ravine is 21 feet. By the Pythagorean Theorem, the length of the zipline is sqrt(20^2+21^2)=sqrt(841)=29.
