A person in a control tower is looking down at an airplane on the runaway that is 78 yards away from the base of the tower.If this tower is 27 yards high, find the angle of depression from the tower to the airplane below.
I did the 27 yards, it didn't say from the airplane so i guessed it was just vertically up from it. I drew a horizontal line across starting from its location because i just went along with it. It just looked right. How would I go about solving this triangle? The given lengths are those of the adjacent and the opposite sides. But then will there be two unknown variables?
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$\begingroup$You have all the information you need. Because you've drawn a square, the top of this square must be the same as the bottom, or 78. You can then use inverse tan to solve for the missing angle:
$$tan^{-1}(\frac{27}{78})$$
$\endgroup$ $\begingroup$Its a perfect rectangle thus according to the definition of tan $tan\theta=\frac{opposite side}{adjacent side}$ $tan\theta=\frac{27}{78}$ thus $\theta=tan^{-1}\frac{27}{78}\approx 18.77$
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