Evaluate: $\displaystyle-{{\left({7}{x}\right)}}^{{2}}\usepackage{cmbright}\Huge\$ if $\displaystyle{x}=-{2}\usepackage{cmbright}\Huge\$

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