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 $a=6$, $b=-9$, $ax+by=6bc-9c^2-12cd-8bf-12cf+16df$, $ax=6bc$, $by=-9c^2$, $x=bc$ e $y=c^2$

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