Hệ pt ⇔$\left \{ {{3x-(\sqrt{3}-1)y=1} \atop {(\sqrt{3}+1)x-(\sqrt{3}+1)y=0}} \right.$
⇔$\left \{ {{3x-(\sqrt{3}-1)y=1} \atop {x=y}} \right.$
⇔$\left \{ {{3x-(\sqrt{3}-1)x=1} \atop {x=y}} \right.$
⇔$\left \{ {{(4x-\sqrt{3})x=1} \atop {x=y}} \right.$
⇔x=y=$\frac{1}{4-\sqrt{3}}=$$\frac{4+\sqrt{3}}{13}$