Set $\displaystyle{{x}}^{{2}}+{5}{x}-{14}\usepackage{cmbright}\Huge\$ equal to 0 and solve the equation by factoring. The solution to this equation will be the domain's excluded values.

$\displaystyle{{x}}^{{2}}+{5}{x}-{14}={0}\usepackage{cmbright}\Huge\$

$\displaystyle{\left({x}+{7}\right)}{\left({x}-{2}\right)}={0}\usepackage{cmbright}\Huge\$

$\displaystyle{x}+{7}={0}\usepackage{cmbright}\Huge\$ or $\displaystyle{x}-{2}={0}\usepackage{cmbright}\Huge\$

$\displaystyle{x}=-{7}\usepackage{cmbright}\Huge\$ or $\displaystyle{x}={2}\usepackage{cmbright}\Huge\$