Standard form of a quadratic equation is $\displaystyle{a}{{x}}^{{2}}+{b}{x}+{c}={0}\usepackage{cmbright}\Huge\$ , so you must rewrite the equation with one side equal to 0. You correctly reordered the terms on the left side, but forgot to subtract $\displaystyle{3}{{x}}^{{2}}\usepackage{cmbright}\Huge\$ from both sides.