Applicare la formula: $x^a=b$$\to \left(x^a\right)^{inverse\left(a\right)}=b^{inverse\left(a\right)}$, dove $a=\frac{1}{2}$, $b=x$, $x^a=b=\sqrt{x+y}=x$, $x=x+y$ e $x^a=\sqrt{x+y}$

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

Applicare la formula: $x+a=b$$\to x=b-a$, dove $a=x$, $b=x^2$, $x+a=b=x+y=x^2$, $x=y$ e $x+a=x+y$