## Intermediate Algebra (6th Edition)

$18a^{3}b^{6}$
We are given the expression $(-6a^{2}b^{3})(-3ab^{3})$. We can group like terms to simplify. $(-6\times-3)\times(a^{2}\times a)\times (b^{3}\times b^{3})$ To simplify the second and third terms, we can use the product rule, which holds that $a^{m}\times a^{n}=a^{m+n}$ (where a is a real number, and m and n are positive integers). $18\times a^{2+1} \times b^{3+3}=18a^{3}b^{6}$