Question

A particular airport has beacons on the ground 5 km out from the start of each runway. An airplane is directly over this beacon and is at an angle of elevation from the runway of 6º Calculate the direct line distance from the airplane to the start of the runway

Answer 1

Let's make a diagram to represents the situation

To find x, we have to use the cosine function, which is equivalent to the ratio between the adjacent leg and the hypotenuse.

$\begin{gathered} \cos 6=\frac{5}{x} \\ x=\frac{5}{\cos 6}\approx5.03 \end{gathered}$

Hence, the distance is 5.03 kilometers, approximately.