an airplane traveling at 400 mph at a cruising altitude of 7.2 begins its descent. if the angle of descent is 1 degree from the horizontal

Question

an airplane traveling at 400 mph at a cruising altitude of 7.2 begins its descent. if the angle of descent is 1 degree from the horizontal, determine the new altitude after 15 min . round to the nearest tenth of a mile.

Answer 1

Assuming the plane goes the same speed during descent, it is going 400 miles/hour along the hypotenuse of a right triangle. The descent distance is the y-component (opposite of angle of descent - the sine)

The new altitude is 7.2 miles - (.25 hours)(400 miles/hour)sin(1°)