Answer
(b)
Work Step by Step
The given expression is a binomial so the only possible factoring techniques that would work are: sum or difference of two cubes, difference of two squares, or factoring out a GCF.
However, the given binomial is neither a difference of two squares nor a sum of difference of two cubes.
Thus, the only factoring techniques that would work are techniques (a) or (b).
Since the leading coefficient of the binomial is negative, then technique (b) will be used.
