Sorry, you answered incorrectly. The correct answer was B. To solve this problem, follow the steps given below.
1. X³+12X-64=0
2. You must factor this prblem first before trying to move on.
X³-4X+16X-64=0
X(X²-4) +16(X²-4)
Since you have a DIFFERENCE OF SQUARES, you must break that down.
(X-2)(X+2)(X+16)
3. Then set all the polynomials equal to 0 and solve.
X-2=0 X=2
X+2=0 X=-2
X+16=0 X=-16
4. Check each answer choice to see if it works.
So your answer is {X=-16;-2;2}