One of the first calculus class problems is the sliding ladder. In this problem, a ladder is resting against a wall when, all of a sudden, it starts sliding down! In this problem you’re solving for dx/dt or the rate at which the point B is moving away from the wall (point C).

Input constraints:

-The rate of slide must be negative for the ladder to slide down

-The initial height of the ladder must be less than the ladders length