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

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

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