$$2x^{2}-5y^{2}=8;x^{2}+2y^{2}=13$$
$x=-3\text{, }y=-\sqrt{2}\approx -1.414213562$
$x=-3\text{, }y=\sqrt{2}\approx 1.414213562$
$x=3\text{, }y=-\sqrt{2}\approx -1.414213562$
$x=3\text{, }y=\sqrt{2}\approx 1.414213562$
