Distance between airplanes An airplane flying north at 200 mi/hr passed over a point on th...

Distance between airplanes An airplane flying north at 200 mi/hr passed over a point on the ground at 2:00 P.M. Another airplane at the same altitude passed over the point at 2:30 P.M., flying east at 400 mi/hr (see the figure).

(a) If t denotes the time in hours after 2:30 P.M., express the distance d between the airplanes in terms of t.

(b) At what time after 2:30 P.M. were the airplanes 500 miles apart?

EXERCISE