66
Step-by-step explanation:
pretty sure it's 66 because the two lengths added together is 66
In your situation you said that
Putting those together, you'd have
because
.
To evaluate the difference quotient, first find each piece on it's own:
because
no matter what your x-value is.
So putting those together:

Remember that the difference quotient is basically finding the slope of something. Since you were given that the slope is 0, the difference quotient should work out to match that.
Answer:
hope it's help you ok have a good day