HELP Please
A ladder 25 feet long is leaning against the wall of a house. The base of the ladder is pulled away from the wall at a rate of 2 feet per second.
(a) What is the velocity of the top of the ladder when the base is given below?
15 feet away from the wall
20 feet away from the wall

Question

HELP Please  
A ladder 25 feet long is leaning against the wall of a house. The base of the ladder is pulled away from the wall at a rate of 2 feet per second.
(a) What is the velocity of the top of the ladder when the base is given below?
15 feet away from the wall
20 feet away from the wall

anonymous · Answer

x^2+y^2=25
2xdx/dt+2ydy/dt=0
i dont know how to finish it