Question

A 25 ft ladder leans against a building. The ladder’s base is 13.5 feet from the building. Find the angle of elevation, which the ladder makes with the ground.

Answer 1

57.3°

Explanation:

A 25 feet ladder leans against a building.

The ladder's base is 13.5 feet from the building.

The ladder, the wall of the building and the ground form a right-angled triangle of:

Hypotenuse = 25 feet

Base = 13.5 feet

We are to find the angle of elevation which the ladder makes with the ground (or rather the angle created by hypotenuse and base)

Let's say the angle = X°

According to a trigonometric equation;

cos X° = adjacent side ÷ hypotenuse =
`(13.5)/(25)` = 0.54

`cos ^(-1) X` = 57.5=3° (Answer rounded up to nearest one decimal place).

∴ The angle of elevation = 57.3°