An airplane is approaching an airport at an altitude of 300 feet. Looking directly down the runway, the pilot sights an angle of depression with a measure of 29 degrees to the near end of the runways, and one with a measure of 7 to the far end of the runway.

Let the perpendicular line dropped drawn from the airplane to ground meet at C. If the airplane is A, the start of the runway B and the end of the runway D, we have two right triangles, ACB and ACD.

The length of the runway is DC - BC = `300/tan 7 - 300/tan 29`

= `300*(1/(tan 7) - 1/(tan 29))`

`~~ 1902.08` feet

**The length of the runway is approximately 1902.08 feet**

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