Side $\displaystyle{\overline{{{A}{D}}}}\usepackage{cmbright}\Huge\$ is part of the bottom left triangle, while $\displaystyle\angle{B}{A}{C}\usepackage{cmbright}\Huge\$ is part of the top right triangle. For triangle ABC, the side opposite $\displaystyle\angle{B}{A}{C}\usepackage{cmbright}\Huge\$ would be $\displaystyle{\overline{{{B}{C}}}}\usepackage{cmbright}\Huge\$ .