The rate of change of a function can be modeled with the following expression:
Where Δx is the change in x value, and Δk(x) is the corresponding change in k(x). We're given the two extremes of x, so we can calculate the change in x to be
To find the change in k(x), we can calculate the values of k(x) at x = -14 and x = -4 and find the difference between them:
So, the rate of change for the function from x = -14 to x = -4 is