Consider the function f(x) = 2 - 7x² on the interval [ - 5, 7]. Find the average or mean slope of the function on this interval, i.e. f(7)-f(-5) 7-(-5) By the Mean Value Theorem, we know there exists a c in the open interval (-5, 7) such that f (c) is equal to this mean slope. For this problem, there is only one c that works. Find it.