\[\left\{ \begin{matrix} y = 3 - x \\ y = 2x\ \ \ \ \ \ \\ \end{matrix} \right.\ \]
\[3 - x = 2x\]
\[3 = 3x\]
\[x = 1\]
\[y(1) = 2 \cdot 1\]
\[y = 2\]
\[Ответ:(1;2).\]