Substituting $\displaystyle{\left(-{2},-{4}\right)}\usepackage{cmbright}\Huge\$ into $\displaystyle{2}{y}-{5}{x}<{3}\usepackage{cmbright}\Huge\$ , you get $\displaystyle{2}{\left(-{4}\right)}-{5}{\left(-{2}\right)}<{3}\usepackage{cmbright}\Huge\$ , or $\displaystyle-{8}+{10}<{3}\usepackage{cmbright}\Huge\$ . This is a true statement, so $\displaystyle{\left(-{2},-{4}\right)}\usepackage{cmbright}\Huge\$ is a solution to the inequality.