posted by amber .
an airplane is flying at an altitude of 3200 feet. an air- traffic controller in the tower keeps constant track of the planes distance from the tower in X feet. express the horizontal distance from the tower to a point directly below the airplane,d, in terms of X.
the distance x is the hypotenuse of a right triangle with legs d and 3200.
d^2 = x^2 - 3200^2