Applicare la formula: $ax+by$$=\left(\frac{a}{mcd\left(a,b\right)}x+\frac{b}{mcd\left(a,b\right)}y\right)mcd\left(a,b\right)$, dove $a=-3$, $b=6$, $ax+by=-3x+6y-8$, $ax=-3x$ e $by=6y$

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