Expert: Sherman D. - 7/14/2004

Question
From the top of a 120-foot-high tower, an air traffic controller observes an airplane on the runway at an angle of depression of 19 degrees. How far from the base of the tower is the airplane? my answer was 349 feet,Is this correct?  

Answer
   |    |     |19 120|       |        |         ____19__

Tan(19) = x/120

x = Tan(19) * 120

x = 41.32 feet from the base.

That was what i got. If you like you can see what other experts give you, and see what the popular answer is, just to make sure if what i have is right or not.

The angle you used would be if you were on the ground looking up, not looking down. The top angle is the angle of depression, and the bottom angle is the angle of altitude.

Also keep in mind that 19 degrees is really close to straight down.

Since i am not really good at word problems, i would definately ask other experts to see what they say.