Answer
$2wr+3-\frac{4}{wr}.$
Work Step by Step
We divide each term of the polynomial by the monomial as follows
$$
\frac{18w^4r^4 + 27w^3r^3 - 36w^2r^2}{ 9w^3r^3}= \frac{18w^4r^4 }{ 9w^3r^3}+ \frac{ 27w^3r^3 }{ 9w^3r^3}+ \frac{ - 36w^2r^2}{ 9w^3r^3} \\
= 2wr+3-\frac{4}{wr}.
$$
