$$\left\{\begin{matrix} 5x+y=10 \\ { x }^{ 2 } -y=8 \end{matrix}\right.$$
$x=\frac{\sqrt{97}-5}{2}\approx 2.424428901\text{, }y=\frac{45-5\sqrt{97}}{2}\approx -2.122144504$
$x=\frac{-\sqrt{97}-5}{2}\approx -7.424428901\text{, }y=\frac{5\sqrt{97}+45}{2}\approx 47.122144504$
