Question

A hang glider is standing at the top of a 3,000 foot cliff. The hang glider jumps off and begins to descend at a constant rate of 50 feet per second, how fast is the area of the triangle formed by the cliff, the hang glider, and the ground changing at the instant when the hang glider is 2,000 feet above the ground?

Answer 1

You need to know the slope of the glider's descent. If he drops straight down, there is no triangle. That is, you need to know his horizontal speed. The vertical drop of 50 ft/s is no good by itself.