Question 43113
<pre><font size = 5><b>
The approach pattern to an airport requires pilots
to set an 11o angle of descent toward a runway. If
a plane is flying at an altitude of 9,500 m, at what
distance (measured along the ground) from the airport
must the pilot decend 

                                 P
                                  ·
                      ·           | 9500 m 
A        ·     11°                |
·---------------------------------
              x                   B

The plane is at P, the Airport is at A,
B is a point on the ground directly under the plane.
We want to find AB, the length of which we call x

9500 is the opposite side to 11°
x is the adjacent side to 11°

  tan(11°) = opposite/adjacent

  tan(11°) = 9500/x

x·tan(11°) = 9500 

         x = 9500/tan(11°)

         x = 48873.26315 m or about 48900 meters.

Edwin
AnlytcPhil@aol.com</pre>