Applicare la formula: $x+a=b$$\to x=b-a$, dove $a=3x$, $b=7$, $x+a=b=3x+\sin\left(y\right)=7$, $x=\sin\left(y\right)$ e $x+a=3x+\sin\left(y\right)$

Applicare la formula: $a=b$$\to inverse\left(a,a\right)=inverse\left(a,b\right)$, dove $a=\sin\left(y\right)$ e $b=7-3x$

Applicare la formula: $\arcsin\left(\sin\left(\theta \right)\right)$$=\theta $, dove $x=y$