$\begin{array}{l}\phantom{\phantom{;}x\phantom{;}+5;}{\phantom{;}x^{2}-7x\phantom{;}+66\phantom{;}\phantom{;}}\\\phantom{;}x\phantom{;}+5\overline{\smash{)}\phantom{;}x^{3}-2x^{2}+31x\phantom{;}+20\phantom{;}\phantom{;}}\\\phantom{\phantom{;}x\phantom{;}+5;}\underline{-x^{3}-5x^{2}\phantom{-;x^n}\phantom{-;x^n}}\\\phantom{-x^{3}-5x^{2};}-7x^{2}+31x\phantom{;}+20\phantom{;}\phantom{;}\\\phantom{\phantom{;}x\phantom{;}+5-;x^n;}\underline{\phantom{;}7x^{2}+35x\phantom{;}\phantom{-;x^n}}\\\phantom{;\phantom{;}7x^{2}+35x\phantom{;}-;x^n;}\phantom{;}66x\phantom{;}+20\phantom{;}\phantom{;}\\\phantom{\phantom{;}x\phantom{;}+5-;x^n-;x^n;}\underline{-66x\phantom{;}-330\phantom{;}\phantom{;}}\\\phantom{;;-66x\phantom{;}-330\phantom{;}\phantom{;}-;x^n-;x^n;}-310\phantom{;}\phantom{;}\\\end{array}$

$x^{2}-7x+66+\frac{-310}{x+5}$