$\begin{array}{l}\phantom{\phantom{;}x\phantom{;}+7;}{\phantom{;}12x\phantom{;}-59\phantom{;}\phantom{;}}\\\phantom{;}x\phantom{;}+7\overline{\smash{)}\phantom{;}12x^{2}+25x\phantom{;}-70\phantom{;}\phantom{;}}\\\phantom{\phantom{;}x\phantom{;}+7;}\underline{-12x^{2}-84x\phantom{;}\phantom{-;x^n}}\\\phantom{-12x^{2}-84x\phantom{;};}-59x\phantom{;}-70\phantom{;}\phantom{;}\\\phantom{\phantom{;}x\phantom{;}+7-;x^n;}\underline{\phantom{;}59x\phantom{;}+413\phantom{;}\phantom{;}}\\\phantom{;\phantom{;}59x\phantom{;}+413\phantom{;}\phantom{;}-;x^n;}\phantom{;}343\phantom{;}\phantom{;}\\\end{array}$

$12x-59+\frac{343}{x+7}$