\[y = - x:\]
\[x^{2} - 2x - 6 = - x\]
\[x^{2} - x - 6 = 0\]
\[x_{1} + x_{2} = 1,\ \ \ x_{1} \cdot x_{2} = - 6\]
\[x = 3,\ \ x = - 2\]
\((3;\ - 3);\ \ \ \ ( - 2;2).\)