Решите систему уравнений способом подстановки: x-y=-2; y+2x=4.

\[\left\{ \begin{matrix} x - y = - 2 \\ y + 2x = 4\ \\ \end{matrix} \right.\ \]

\[\left\{ \begin{matrix} y = x + 2\ \ \ \ \ \ \ \ \ \ \ \\ x + 2 + 2x = 4 \\ \end{matrix} \right.\ \]

\[3x + 2 = 4\]

\[3x = 2\]

\[x = \frac{2}{3}.\]

\[y = x + 2 = \frac{2}{3} + 2 = 2\frac{2}{3}.\]

\[Ответ:\left( \frac{2}{3};2\frac{2}{3} \right).\]