## Precalculus (6th Edition)

$3z^3w^2(-z^2-6w^2) \text{ or }-3z^3w^2(z^2+6w^2)$
The GCF of the coefficients is $3$. The GCF of the literal coefficients (the variables) is the one with the lowest exponent for each variable. Thus, the GCF for the variables is $z^3w^2$. The GCF is $3z^3w^2$. Factor out the GCF to obtain: $-3z^5w^2-18z^3w^4=3z^3w^2(-z^2-6w^2)$ Alternatively, $-3z^3w^2$ can be factored out to obtain: $-3z^5w^2-18z^3w^4=-3z^3w^2(z^2+6w^2)$