Answer
$(x+6)(x^{2}-2)$
Work Step by Step
In step 1, use the associative property in order to group and isolate terms from each set of parentheses. Next, find the greatest common factors of each new group and pull them out. Then regroup the terms and combine all the terms to get the final answer.
$(x^{3}+6x^{2}) - (2x+12)$
$= x^{2}(x+6) - 2(x+6)$
$= (x+6)(x^{2}-2)$
