A 10 foot ladder leans against a vertical wall, and the bottom of the ladder slides away from the wall at a rate of 2 ft/s. At what rate is the angle between the ladder and the ground changing when the top of the ladder is 5 feet above the ground?

Question

anonymous · Answer

|dw:1350916481270:dw|

anonymous · Answer

nice $\theta$!!

anonymous · Answer

differentiate both sides with respect to time.  use the second equation to find any unknowns...(dy/dt, x)  
Alternately, solve the second equation for y in terms of x and sub.s into the first equation.   Your choice:)

anonymous · Answer

any questions about differentiating?  or substituting?

anonymous · Answer

No, I think I understand. Thanks :)

anonymous · Answer

sure;)

anonymous · Answer

Is the correct answer to this question -2(sqrt75) / 5?   Just want to make sure I'm doing everything right.