Correct. Since the line $\displaystyle{y}=\frac{{1}}{{5}}{x}+{7}\usepackage{cmbright}\Huge\$ has slope $\displaystyle\frac{{1}}{{5}}\usepackage{cmbright}\Huge\$ , any line perpendicular to it will have slope -5 (the opposite reciprocal of $\displaystyle\frac{{1}}{{5}}\usepackage{cmbright}\Huge\$ ).