Applicare la formula: $\frac{a^m}{a^n}$$=a^{\left(m-n\right)}$, dove $a^n=x^3$, $a^m=x^7$, $a=x$, $a^m/a^n=\frac{45x^7y^9}{5x^3y^4}$, $m=7$ e $n=3$

Applicare la formula: $\frac{a^m}{a^n}$$=a^{\left(m-n\right)}$, dove $a^n=y^4$, $a^m=y^9$, $a=y$, $a^m/a^n=\frac{45x^{4}y^9}{5y^4}$, $m=9$ e $n=4$

Applicare la formula: $\frac{ab}{c}$$=\frac{a}{c}b$, dove $ab=45x^{4}y^{5}$, $a=45$, $b=x^{4}y^{5}$, $c=5$ e $ab/c=\frac{45x^{4}y^{5}}{5}$