1. The problem statement, all variables and given/known data An 18 meter ladder is sliding down a vertical wall at a rate of 2.5 m/s. Find the speed of the lower end of the ladder when it is 12 meters from the wall. 2. Relevant equations Pythagorean Theorem 3. The attempt at a solution Let h = height of the wall L = length of the ladder b = distance from the wall to the bottom of the ladder dh/dt = 2.5 m/s db/dt = ? when b = 12 18^2 = 12^2 + h^2 h = rad(180) L^2 = h^2 + b^2 18^2 = 2h dh/dt + 2b db/dt 0 = 2h (2.5) + 2(12) db/dt 0 = 2[rad(180)] (2.5) + 2(12)(db/dt) -2.79 m/s = db/dt Could anyone verify that this is right? Please correct me if I'm wrong.