## Intermediate Algebra for College Students (7th Edition)

$3x^{2}(x-2)(5x-3)$
$15x^{4}-39x^{3}+18x^{2}\qquad$...factor out the common term, $3x^{2}$. $=3x^{2}(5x^{2}-13x+6)$ Two factors of $ac=30$, whose sum is $b=-13$ are$-10$ and $-3$. Rewrite the middle term and factor in pairs. $3x^{2}(5x^{2}-13x+6)$ $=3x^{2}(5x^{2}-10x-3x+6)$ $=3x^{2}[5x(x-2)-3(x-2)]$ =$3x^{2}(x-2)(5x-3)$