Question

$-27x^{3}+125=$

Explanation:

Step1: Rearrange the terms

$125 - 27x^3$

Step2: Rewrite as difference of cubes

$5^3 - (3x)^3$

Step3: Apply difference of cubes formula

Recall $a^3 - b^3=(a-b)(a^2+ab+b^2)$, here $a=5$, $b=3x$
$(5 - 3x)(5^2 + 5\cdot3x + (3x)^2)$

Step4: Simplify the quadratic term

$(5 - 3x)(25 + 15x + 9x^2)$

Answer:

$(5 - 3x)(9x^2 + 15x + 25)$