To solve the system of equations $$\begin{cases} f_1(x,y,z)&=0\\f_2(x,y,z)&=0\\f_3(x,y,z)&=0 \end{cases}$$ enter $f_1(x,y,z)=0$ in the $Eq_1$ box, $f_2(x,y,z)=0$ in the $Eq_2$ box and $f_3(x,y,z)=0$ in the $Eq_3$ box, only with the variables $x,y,z$