Multiply both sides of the equation by the multiplicative inverse of $\displaystyle-\frac{{1}}{{4}}\usepackage{cmbright}\Huge\$ , which is $\displaystyle-{4}\usepackage{cmbright}\Huge\$ :

$\displaystyle{\left(-{4}\right)}{\left(-\frac{{1}}{{4}}\right)}{x}={\left(-{4}\right)}{6}\usepackage{cmbright}\Huge\$ . Simplifying, $\displaystyle{\left(\frac{{4}}{{4}}\right)}{x}=-{24}\usepackage{cmbright}\Huge\$ or $\displaystyle{x}=-{24}\usepackage{cmbright}\Huge\$ .