$\begin{array}{l}\phantom{\phantom{;}3x\phantom{;}-4;}{\phantom{;}3x^{2}+4x\phantom{;}+5\phantom{;}\phantom{;}}\\\phantom{;}3x\phantom{;}-4\overline{\smash{)}\phantom{;}9x^{3}\phantom{-;x^n}-x\phantom{;}-28\phantom{;}\phantom{;}}\\\phantom{\phantom{;}3x\phantom{;}-4;}\underline{-9x^{3}+12x^{2}\phantom{-;x^n}\phantom{-;x^n}}\\\phantom{-9x^{3}+12x^{2};}\phantom{;}12x^{2}-x\phantom{;}-28\phantom{;}\phantom{;}\\\phantom{\phantom{;}3x\phantom{;}-4-;x^n;}\underline{-12x^{2}+16x\phantom{;}\phantom{-;x^n}}\\\phantom{;-12x^{2}+16x\phantom{;}-;x^n;}\phantom{;}15x\phantom{;}-28\phantom{;}\phantom{;}\\\phantom{\phantom{;}3x\phantom{;}-4-;x^n-;x^n;}\underline{-15x\phantom{;}+20\phantom{;}\phantom{;}}\\\phantom{;;-15x\phantom{;}+20\phantom{;}\phantom{;}-;x^n-;x^n;}-8\phantom{;}\phantom{;}\\\end{array}$

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