Applicare la formula: $\frac{a}{b}$$=\frac{a}{b}$, dove $a=6$, $b=4$ e $a/b=\frac{6}{4}$

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

Applicare la formula: $ab$$=ab$, dove $ab=2\cdot 2$, $a=2$ e $b=2$

Applicare la formula: $ab$$=ab$, dove $ab=-5\cdot 3$, $a=-5$ e $b=3$