Question

A 24-foot ladder leans against a building. The foot

of the ladder is 7 ft from the building. Find the
measure of the angle which the ladder makes with
the level ground.

Answer 1

73°

Explanation:

Here we use trigonometry to find the angle. The building and the ground form a perpendicular angle, with the ladder acting as the hypotenuse, we get a right angle. We know the length of adjacent leg from the angle, and the length of the hypotenuse. In this case, we use cosine since cos = adjacent length/hypotenuse length. So cos x= 7/24. To isolate x, we use the inverse function of cos, cos^-1. Then x= cos^-1 (7/24) or 73°.