Respuesta :

You need to calculate the following expression:

   f(b) - f(a)                                          [(10)^2-3(10)-4]-[(7)^2-3(7) -4]
 --------------- , which in this case is:   ------------------------------------------
       b - a                                                              10-7



Be sure to do the calculations inside each set of square brackets separately BEFORE attempting the subtraction in  [(10)^2-3(10)-4]   -   [(7)^2-3(7) -4]

By the way:  You mean "average rate of change," not "average of change."