$$(x)=11xy+5x+7y=(x)=7xy+3y-4x$$
$x=11xy+5x+7y\text{ and }11xy+5x+7y=x\text{ and }x=7xy-4x+3y$
$\left\{\begin{matrix}x=0\text{, }&y=0\\x=-\frac{47}{83}\approx -0.56626506\text{, }&y=\frac{47}{16}\end{matrix}\right.$
$\left\{\begin{matrix}y=0\text{, }&x=0\\y=\frac{47}{16}\text{, }&x=-\frac{47}{83}\end{matrix}\right.$