Question

A ramp leading into a building makes a 15o angle with the ground. The end of the ramp is 10 feet from the base of the building.

Approximately how long is the ramp? Round to the nearest tenth.

Answer 1

cos15=10/r

r=10/cos15

r=10.4 ft

Answer 2

The ramp is 10.4 ft long

Explanation:

A rectangle triangle is formed in which the ramp is the hypotenuse, the distance between the end of the ramp and the base of the building is one of the sides (its measure is 10 ft) and the angle between this distance and the hypotenuse is 15° (let's call it angle A).

From cosine definition:

cos(A) = (adjacent side)/(hypotenuse)

hypotenuse = 10 ft/cos(15°) = 10.4 ft