$\begin{array}{l}\phantom{\phantom{;}5x\phantom{;}+4;}{\phantom{;}4x^{2}+6x\phantom{;}-1\phantom{;}\phantom{;}}\\\phantom{;}5x\phantom{;}+4\overline{\smash{)}\phantom{;}20x^{3}+46x^{2}+19x\phantom{;}+4\phantom{;}\phantom{;}}\\\phantom{\phantom{;}5x\phantom{;}+4;}\underline{-20x^{3}-16x^{2}\phantom{-;x^n}\phantom{-;x^n}}\\\phantom{-20x^{3}-16x^{2};}\phantom{;}30x^{2}+19x\phantom{;}+4\phantom{;}\phantom{;}\\\phantom{\phantom{;}5x\phantom{;}+4-;x^n;}\underline{-30x^{2}-24x\phantom{;}\phantom{-;x^n}}\\\phantom{;-30x^{2}-24x\phantom{;}-;x^n;}-5x\phantom{;}+4\phantom{;}\phantom{;}\\\phantom{\phantom{;}5x\phantom{;}+4-;x^n-;x^n;}\underline{\phantom{;}5x\phantom{;}+4\phantom{;}\phantom{;}}\\\phantom{;;\phantom{;}5x\phantom{;}+4\phantom{;}\phantom{;}-;x^n-;x^n;}\phantom{;}8\phantom{;}\phantom{;}\\\end{array}$

$4x^{2}+6x-1+\frac{8}{5x+4}$