Answer
$\color{blue}{(3y^3+5z^2)(9y^6-15y^3z^2+25z^4)}$
Work Step by Step
With $27y^9=(3y^3)^3$ and $125z^6=(5z^2)^3$, the given polynomial is equivalent to:
$=(3y^3)^3+(5z^2)^3$
Factor using the formula $a^3+b^3=(a+b)(a^2-ab+b^2)$ with $a=3y^3$ and $b=5z^2$ to obtain:
$=(3y^3+5z^2)[(3y^3)^2-(3y^3)(5z^2) + (5z^2)^2]
\\=\color{blue}{(3y^3+5z^2)(9y^6-15y^3z^2+25z^4)}$