Applicare la formula: $x\left(a+b\right)$$=xa+xb$, dove $a=\frac{4}{5}x$, $b=3$, $x=\frac{1}{5}x-\frac{2}{5}$ e $a+b=\frac{4}{5}x+3$

Applicare la formula: $x\left(a+b\right)$$=xa+xb$, dove $a=\frac{1}{5}x$, $b=-\frac{2}{5}$, $x=\frac{4}{5}x$ e $a+b=\frac{1}{5}x-\frac{2}{5}$

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

Combinazione di termini simili $\frac{4}{5}\cdot -\frac{2}{5}x$ e $\frac{3}{5}x$

Applicare la formula: $\frac{a}{b}\frac{c}{f}$$=\frac{ac}{bf}$, dove $a=4$, $b=5$, $c=1$, $a/b=\frac{4}{5}$, $f=5$, $c/f=\frac{1}{5}$ e $a/bc/f=\frac{4}{5}\cdot \frac{1}{5}x^2$