I need to decide for which $x,y,z$ the following equation system is met:
$$ 1+x+y=xy $$ $$ 2+y+z=yz $$ $$5+z+x=zx$$
I can see that $x=0, y=0, z=0$ is not a solution.
I tried to divide first equation with $xy$, second with $yz$, third with $zx$ and then substitute $\frac 1x=a$, $\frac 1y=b$ and $\frac 1z=c$ but it didn't work out.
Hint: rewrite the system as follow.
\begin{align} (x-1)(y-1)&=2 \\ (y-1)(z-1)&=3 \\ (z-1)(x-1)&=6 \end{align}