Question

A ladder leaning against a building makes an angle of 78 degrees with the ground. The foot of the ladder is 5 feet from the building. How long is the ladder?

Answer 1

9514 1404 393

Answer:

24 feet

Explanation:

The side adjacent to the angle is given, and the hypotenuse of the triangle is the unknown. The cosine relation applies:

Cos = Adjacent/Hypotenuse

hypotenuse = ladder length = (5 ft)/cos(78°) ≈ 24.0 ft

The ladder is about 24 feet long.