Question

A helicopter takes off from the ground 800 feet from the base of a building. It flies in a straight line directly to the top of the building. If the building is 160 feet tall, what angle did the helicopter take off from? Round the answer to the nearest whole degree.

Answer 1

Answer:

11.3°

Step-by-step explanation:

Refer the attached figure .

Height of building i.e. AB = 160 feet.

A helicopter takes off from the ground 800 feet from the base of a building i.e. BC = 800 ft.

We are required to find what angle did the helicopter take off from i.e. ∠ACB

We will use trigonometric ratio .

$tan\theta = \frac{Perpendicular}{Base}$

$tan\theta = \frac{AB}{BC}$

$tan\theta = \frac{160}{800}$

$tan\theta = \frac{1}{5}$

$tan\theta = 0.2$

$\theta =tan^{-1} 0.2$

$\theta =11.3^{\circ}$

Thus the  angle at which  the helicopter take off from is 11.3°