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

Applicare la formula: $\frac{a}{a}$$=1$, dove $a=x+1$ e $a/a=\frac{\left(x^2-5x\right)\left(x+1\right)}{\left(x+1\right)\left(x^2+3x\right)}$

Applicare la formula: $\frac{a}{a}$$=1$, dove $a=x+1$ e $a/a=\frac{\left(x^2-5x\right)\left(x+1\right)}{\left(x+1\right)\left(x^2+3x\right)}$