Geometry question

Question

A ramp needs to reach a point that is 1.5 feet above the ground . If the ramp is to make a 20 degrees angle with the ground , how long will the ramp be?

Answer 1

The ramp, starting point and ending point form a right triangle, with the ramp as the hypotenuse. The 20 degree is between the hypotenuse and an adjacent leg. The 1.5 foot point above the ground is opposite the 20 degree angle. So the sin(20) = opposite/hypotenuse = 1.5/hypotenuse, where hypotenuse is the length of the ramp and opposite is 15.

sin(20) = 1.5/ramp length