The answer is -9, because of PEMDAS
Well, that's incorrect because according to the Order of Operation [GEMS\BOMDAS\PEMDAS etc.], that -7 has to be distributed amongst all the other terms in parentheses. Besides, you did the wrong operation when you inserted that subtraction symbol in substitution of the parentheses, which means to MULTIPLY. So, the order goes as follows:
12 - 7[72]
-504 + 12 = -492 [OR 12 - 504]
-492 is your answer. You get it now?
It should look like a parabola with the part below x-axis cut off. the left side starts from x=-1, opening upward & to the left, the right side starts from x=2, opening upward and to the right.