Question

An observer (O) is located 900 feet from a building (B). The observer notices a helicopter (H) flying at a 49° angle of elevation from his line of sight. How high is the helicopter flying over the building?

Answer 1

SOHCAHTOA
you can use one of the following to find your answer:
\[sin(49)=\frac{o}{h}=\frac{h}{hypotenuse}\]
\[cos(49)=\frac{a}{h}=\frac{900ft}{hypotenuse}\]
\[tan(49)=\frac{o}{a}=\frac{h}{900ft}\]
use one of these to calculate the height. Good luck