You may have correctly simplified this to $\displaystyle-{2}{\left|{b}-{3}\right|}={12}\usepackage{cmbright}\Huge\$ , but then treated it as if it were $\displaystyle{\left|-{2}{b}-{3}\right|}={12}\usepackage{cmbright}\Huge\$ , solving $\displaystyle-{2}{b}-{3}={12}\usepackage{cmbright}\Huge\$ or $\displaystyle-{2}{b}-{3}=-{12}\usepackage{cmbright}\Huge\$ . The correct simplification would be $\displaystyle{\left|{b}-{3}\right|}=-{6}\usepackage{cmbright}\Huge\$ . The correct answer is no solution.