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

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