# Answer

Given our assumptions, we can model the problem as a right triangle with two
known and one unknown sides. This is because the line of sight is tangent to
the earth's surface. If you refer to the
diagram, you will see that the length of the hypotenuse
(the earth's radius plus Kitty Hawk's height) and one of the other sides (the
earth's radius) are known, and that the length of the unknown side is exactly
the line-of-sight distance that we want to determine.
Given this model, our method is clear. We will exploit the Pythagorean Theorem
to solve for the unknown side in terms of the two known sides.

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*Joseph L. Zachary *

Hamlet Project

Department of Computer Science

University of Utah