When $\displaystyle{x}={0}\usepackage{cmbright}\Huge\$ , $\displaystyle{5}{\left({0}\right)}+{10}{y}={15}\usepackage{cmbright}\Huge\$ , so $\displaystyle{10}{y}={15}\usepackage{cmbright}\Huge\$ and $\displaystyle{y}={1.5}\usepackage{cmbright}\Huge\$ . When $\displaystyle{x}={1}\usepackage{cmbright}\Huge\$ , $\displaystyle{5}{\left({1}\right)}+{10}{y}={15}\usepackage{cmbright}\Huge\$ , so $\displaystyle{10}{y}={10}\usepackage{cmbright}\Huge\$ and $\displaystyle{y}={1}\usepackage{cmbright}\Huge\$ . When $\displaystyle{x}={2}\usepackage{cmbright}\Huge\$ , $\displaystyle{5}{\left({2}\right)}+{10}{y}={15}\usepackage{cmbright}\Huge\$ , so $\displaystyle{10}{y}={5}\usepackage{cmbright}\Huge\$ and $\displaystyle{y}={0.5}\usepackage{cmbright}\Huge\$ .