A16 foot ladder is leaning against a wall. if the top of the ladder slides down the wall at a rate of 3 feet per second, how fast is the bottom of the ladder moving along the ground when the bottom of the ladder is 4 feet from the wall? leave your answer in exact form, simplified as much as possible. do not include units.

11.625

Explanation:

L = length of the ladder = 16 ft

= rate at which top of ladder slides down = - 3 ft/s

= rate at which bottom of ladder slides

y = distance of the top of ladder from the ground

x = distance of bottom of ladder from wall = 4 ft

Using Pythagorean theorem

L² = x² + y²

16² = 4² + y²

y = 15.5 ft

Also using Pythagorean theorem

L² = x² + y²

Taking derivative both side relative to "t"

= 11.625 ft/s