\[\left\{ \begin{matrix} x - y = - 2 \\ x - 2y = 4 \\ \end{matrix} \right.\ \text{\ \ \ \ \ }\]
\[\left\{ \begin{matrix} x = y - 2\ \ \ \ \ \ \ \ \ \\ y - 2 - 2y = 4 \\ \end{matrix} \right.\ \text{\ \ \ \ \ \ }\]
\[\left\{ \begin{matrix} x = y - 2 \\ - y = 6\ \ \ \ \\ \end{matrix} \right.\ \text{\ \ \ \ \ \ }\]
\[\left\{ \begin{matrix} y = - 6 \\ x = - 8 \\ \end{matrix} \right.\ \]
\[Проверка:\ \]
\[\left\{ \begin{matrix} - 8 - ( - 6) = - 2\ \ \\ - 8 - 2 \cdot ( - 6) = 4 \\ \end{matrix} \right.\ \text{\ \ \ \ \ }\]
\[\left\{ \begin{matrix} - 2 = - 2 \\ 4 = 4\ \ \ \ \ \ \\ \end{matrix} \right.\ \Longrightarrow верно.\]
\[Ответ:( - 8;\ - 6).\]