Question

Consider the triangle formed by the side of the house, ladder, and the ground. Find the rate at which the area of the triangle is changing when the base of the ladder is 24 feet from the wall.

Answer 1

I know the area formula,\[A=\frac{1}{2}bh\]I also know the derivative of this formula is,\[\frac{dA}{dt}=\frac{1}{2}(h\frac{db}{dt}+b\frac{dh}{dt})\]From here h=7, b=24, db/dt=2, and dh/dt=6.857. I get an answer but its not correct?

Answer 2

6.857 is ft/sec which is representing how fast the ladder is falling down the wall if it helps.

Answer 3

I guess, your process is absolutely correct.. You should get 89.284 as the final answer.

Answer 4

Thats what I thought but its wrong somehow.. It doesn't give me the correct answer, just says its wrong.

Answer 5

I got 89.28571429 using the exact number for 6.857 (48/7). 89.286 should be perfectly accurate but its not -_- Unless I'm using the formula wrong some how.