Treat the division as a fraction, rationalize the denominator by multiplying both the numerator and the denominator by the complex conjugate of the denominator, if possible simplify.

$\displaystyle\frac{{{7}-{i}}}{{{2}-{i}}}={\left(\frac{{{7}-{i}}}{{{2}-{i}}}\right)}\cdot{\left(\frac{{{2}+{i}}}{{{2}+{i}}}\right)}=\frac{{{14}+{7}{i}-{2}{i}-{{i}}^{{2}}}}{{{4}+{2}{i}-{2}{i}-{{i}}^{{2}}}}\usepackage{cmbright}\Huge\$

$\displaystyle=\frac{{{15}+{5}{i}}}{{{5}}}={\left(\frac{{{3}+{i}}}{{{1}}}\right)}\cdot{\left(\frac{{5}}{{5}}\right)}={3}+{i}\usepackage{cmbright}\Huge\$