Answer
$(x-3)(x^2+3x+9)$
Work Step by Step
Since $27=3^3$, the given expression is equivalent to:
$=x^3-3^3$
The expression above is a difference of two cubes.
Factor using the formula $a^3-b^3=(a-b)(a^2+ab+b^2)$ with $a=x$ and $b=3$ to obtain:
$=(x-3)(x^2+x(3) + 3^2)
\\=(x-3)(x^2+3x+9)$
