Answer: The ladder is sliding down the wall at a rate of 
Step-by-step explanation:
Since we have given that
Length of ladder = 25 foot
Distance from the wall to the bottom of ladder = 15 feet
Let base be 'x'.
Let length of wall be 'y'.
So, by pythagorus theorem, we get that


Now, the equation would be

Differentiating w.r.t x, we get that

Hence, the ladder is sliding down the wall at a rate of 