Question

A ladder 10ft long rests against a vertical wall. If the bottom of the ladder slides away from the wall at a speed of 2ft/sec , how fast is the top of the ladder sliding down the wall when the bottom of the ladder is 6ft from the wall?

Answer 1

away from the wall at a speed of 2ft/sec=dx/dt

x^2 +h^2 =100
(2x )dx/dt + 2h dh/dt= 0
2h dh/dt=-2x dx/dt
dh/dt= -x/h dx/dt
dh/dt= -6/8 * 2
dh/dt= -3/2

Answer 2

I follow you for the first 3 steps, but my prof shows:

2x+2y =0
2(6)(2) + 2(8) = 0
16 dy/dt = -24
-1.5 ft sec

Answer 3

-3/2=-1.5

Answer 4

Im so confused as to where he got the 2 & 8

Answer 5

in my second step

Answer 6

follow my steps