Correct. Use FOIL.

$\displaystyle{\left({6}+{i}\right)}{\left(-{8}+{i}\right)}={6}{\left(-{8}\right)}+{6}{\left({i}\right)}+{i}{\left(-{8}\right)}+{i}{\left({i}\right)}=-{48}+{6}{i}-{8}{i}+{{i}}^{{2}}\usepackage{cmbright}\Huge\$

$\displaystyle=-{48}-{2}{i}+{\left(-{1}\right)}=-{49}-{2}{i}\usepackage{cmbright}\Huge\$

The real part is $\displaystyle-{49}\usepackage{cmbright}\Huge\$ .