Answer:
C. x² − 8x + 24 − 72/(x+3)
Explanation:
See attached picture for long division method.
Logically, we know x³ − 5x² factors to x² (x − 5). Since x + 3 isn't a factor, we know the remainder isn't 0. So we can narrow the options down to A or C.
One way to find the remainder is through long division. Or, since this is multiple choice, we multiply the options by x + 3 and see which one results in an answer of x³ − 5x².
(x + 3) (x² − 8x + 24 − 72/(x+3))
(x + 3) (x² − 8x + 24) − 72
x³ − 8x² + 24x + 3x² − 24x + 72 − 72
x³ − 5x²