$\begin{array}{l}\phantom{\phantom{;}5x\phantom{;}+2;}{\phantom{;}4x^{2}-4x\phantom{;}-3\phantom{;}\phantom{;}}\\\phantom{;}5x\phantom{;}+2\overline{\smash{)}\phantom{;}20x^{3}-12x^{2}-23x\phantom{;}-14\phantom{;}\phantom{;}}\\\phantom{\phantom{;}5x\phantom{;}+2;}\underline{-20x^{3}-8x^{2}\phantom{-;x^n}\phantom{-;x^n}}\\\phantom{-20x^{3}-8x^{2};}-20x^{2}-23x\phantom{;}-14\phantom{;}\phantom{;}\\\phantom{\phantom{;}5x\phantom{;}+2-;x^n;}\underline{\phantom{;}20x^{2}+8x\phantom{;}\phantom{-;x^n}}\\\phantom{;\phantom{;}20x^{2}+8x\phantom{;}-;x^n;}-15x\phantom{;}-14\phantom{;}\phantom{;}\\\phantom{\phantom{;}5x\phantom{;}+2-;x^n-;x^n;}\underline{\phantom{;}15x\phantom{;}+6\phantom{;}\phantom{;}}\\\phantom{;;\phantom{;}15x\phantom{;}+6\phantom{;}\phantom{;}-;x^n-;x^n;}-8\phantom{;}\phantom{;}\\\end{array}$

$4x^{2}-4x-3+\frac{-8}{5x+2}$