Answer: C x = -2
Explanation:
[Add 72 on both sides]
[Factorise Left Hand Side of equation to get 3 on one side of a bracket]
[Divide each side by 3 to just get the brackets and the x's on one side]
[Minus 24 on both side as the equation must = 0]
[Solve the square on the left hand side]
[Solve for x on left hand side - two possible answers]
[The answer '12' is not in the option for the question so '-2' is the answer]