Applicare la formula: $a+\frac{b}{c}$$=\frac{b+ac}{c}$, dove $a=5x$, $b=-6$, $c=x$, $a+b/c=5x+\frac{-6}{x}$ e $b/c=\frac{-6}{x}$

Applicare la formula: $x\cdot x$$=x^2$

Applicare la formula: $\frac{a}{b}\frac{c}{f}$$=\frac{ac}{bf}$, dove $a=1$, $b=4$, $c=-6+5x^2$, $a/b=\frac{1}{4}$, $f=x$, $c/f=\frac{-6+5x^2}{x}$ e $a/bc/f=\frac{1}{4}\left(x^5-9x^3+4\right)\frac{-6+5x^2}{x}$

Applicare la formula: $1x$$=x$, dove $x=-6+5x^2$