## Precalculus (6th Edition)

$\color{blue}{(5x-3)(25x^2+15x+9)}$
With $125x^3=(5x)^3$ and $27=3^3$, the given polynomial is equivalent to: $=(5x)^3-3^3$ Factor using the formula $a^3-b^3=(a-b)(a^2+ab+b^2)$ with $a=5x$ and $b=3$ to obtain: $=(5x-3)[(5x)^2+(5x)(3) + 3^2) \\=\color{blue}{(5x-3)(25x^2+15x+9)}$