[m]\left\{\begin {matrix}y=2-x\\2x^2+x\cdot (2-x)+(2-x)^2=16\end {matrix}\right.[/m]
[m]\left\{\begin {matrix}y=2-x\\2x^2+2x-x^2+4-4x+x^2=16\end {matrix}\right.[/m]
[m]\left\{\begin {matrix}y=2-x\\2x^2-2x-12=0\end {matrix}\right.[/m]
[m]\left\{\begin {matrix}y=2-x\\x^2-x-6=0\end {matrix}\right.[/m]
D=(-1)^2-4*(-6)=25
[m]\left\{\begin {matrix}y_{1}=2-(-2)\\x_{1}=-2\end {matrix}\right.[/m] или[m]\left\{\begin {matrix}y_{2}=2-3\\x_{2}=3\end {matrix}\right.[/m]
[m]\left\{\begin {matrix}y_{1}=4\\x_{1}=-2\end {matrix}\right.[/m] или[m]\left\{\begin {matrix}y_{2}=-1\\x_{2}=3\end {matrix}\right.[/m]