assuming ya mean
[tex]\frac{16x^4-24x^3+20}{-4x}[/tex]
remember
[tex]\frac{a+b}{c}=\frac{a}{c}+\frac{b}{c}[/tex]
and
[tex]\frac{x^m}{x^n}=x^{m-n}[/tex]
so
[tex]\frac{16x^4-24x^3+20}{-4x}=[/tex]
[tex]\frac{16x^4}{-4x}+\frac{-24x^3}{-4x}+\frac{20}{-4x}=[/tex]
[tex]-4x^3+6x^2+\frac{-5}{x}=[/tex]
[tex]-4x^3+6x^2-\frac{5}{x}[/tex]
that's the best I can do