If you add 4 to both sides you will find that the solution to this inequality is $\displaystyle{a}>{3}\usepackage{cmbright}\Huge\$ . However, the given graph represents the inequality $\displaystyle{a}<{3}\usepackage{cmbright}\Huge\$ . The correct answer is $\displaystyle{a}+{3}<{6}\usepackage{cmbright}\Huge\$ .