解方程： A={x2+xy+y2=2x+y=433x2+z2+xz=2y2+z2+yz=2A = \begin{cases} x^{2}+xy+y^{2}=2\\ x+y=\frac{4 }{3}\sqrt{3}\\x^{2}+z^{2}+xz=\sqrt{2}\\y^{2}+z^{2}+yz=\sqrt{2}\end{cases}A=⎩⎨⎧x2+xy+y2=2x+y=343x2+z2+xz=2y2+z2+yz=2
