Y-3x=1x^2-2xy+y^2=9Решите систему

[latex]x^{2}-2xy+y^{2}=(x+y)^{2}=9 \\ x+y=3,x+y=-3[/latex] получаем 2 подсистемы уравнений: [latex] \left \{ {{y-3x=1} \atop {x+y=3}} \right. [/latex] и  [latex] \left \{ {{y-3x=1} \atop {x+y=-3}} \right. [/latex] 1)  [latex]\left \{ {{y-3x=1} \atop {x+y=3}} \right. \left \{ {{y=1+3x} \atop {x+1+3x=3}} \right. \left \{ {{y=1+3x} \atop {4x=2}} \right. \left \{ {{y= \frac{5}{2}} \atop {x=\frac{1}{2}}} \right. [/latex] 2)  [latex]\left \{ {{y-3x=1} \atop {x+y=-3}} \right. \left \{ {{y=1+3x} \atop {x+1+3x=-3}} \right. \left \{ {{y=1+3x} \atop {4x=-4}} \right. \left \{ {{y=-2} \atop {x=-1} \right. [/latex]