Incorrect. Check again to make sure that each pair of polynomials has the same set of terms. Note that the order of the terms in a polynomial does not matter when you are looking for corresponding like terms; $\displaystyle{2}{a}{b}+{3}{c}\usepackage{cmbright}\Huge\$ is the same as $\displaystyle{3}{c}+{2}{a}{b}\usepackage{cmbright}\Huge\$ .