[tex] \frac{-72x^5+48x^4-36x^3}{(-4x)^2}= \frac{-72x^5+48x^4-36x^3}{16x^2}= \frac{4x^2(-18x^3+12x^2-9x)}{4*4x^2}= \\=\frac{-18x^3+12x^2-9x}{4}=\frac{-18x^3}{4}+\frac{12x^2}{4}-\frac{9x}{4}=-\frac{9x^3}{2}+3x^2-\frac{9x}{4}=\\=x(-\frac{9x^2}{2}+3x-\frac{9}{4})[/tex]
