I I can not get this Q to come out right what am I missing?

Find the absolute maximum and minimum values of the function over the indicated interval, and indicate the x-values at which they occur. ((xx) =3x - 3x - 3x +7:[-1,2] The absolute maximum value is at x = (Round to two decimal places as needed. Use a comma to separate answers as needed.) The absolute minimum value isat x =] (Round to two decimal places as needed. Use a comma to separate answers as needed.)