1
$\left\{\begin{matrix} (x+y)\sqrt{x^2+7}+y\sqrt{2y^2+1}=xy+2y^2 & \\2x\sqrt{x+y }+(x+y)\sqrt{2y^2+1}=3xy-x2 & \end{matrix}\right.$
2
$\left\{\begin{matrix} x+\sqrt{x^2-7}-\sqrt{y^2+24}=2 & \\4\sqrt{x^2-7}-\sqrt{y^2+24}=7y & \end{matrix}\right.$
- githenhi512 yêu thích