## Algebra: A Combined Approach (4th Edition)

$-6x^{3}+6x^{2}-7x$
$-4x^{3}+4x^{2}-4x-(2x^{3}-2x^{2}+3x)=-4x^{3}+4x^{2}-4x-2x^{3}+2x^{2}-3x=-4x^{3}-2x^{3}+4x^{2}+2x^{2}-4x+2x^{2}-3x-4x=-6x^{3}+6x^{2}-7x$ First remove parentheses, then group like terms and then add /subtract.