Question

A plane at an altitude of 7000 ft is flying in the direction of an island . If an angle of depression is 21 ° from the plane to the island , what is the horizontal distance until the plan flies over the island ?

Answer 1

The horizontal distance until the plan flies over the island is 2687.05 feet approximately.

Solution:

Given that, A plane at an altitude of 7000 ft is flying in the direction of an island

An angle of depression is 21 degree from the plane to the island

We have to find what is the horizontal distance until the plan flies over the island  

The diagram is attached below

Assume as shown in the diagram , now we can use the right angle triangle property

$\tan (21)=\frac{\text {distance between plane and point above island}}{\text {height of plane}}$

$\tan (21)=\frac{\text {distance between plane and point above island}}{7000}$

$\text { Distance between plane and point above island }=7000 \times \tan (21)$

$=7000 \times 0.38386=2687.0482$

Hence, the distance between plane and point above island is 2687.05 feet approximately.