\[\frac{x - 3}{2} = \frac{2x}{7}\]
\[7 \cdot (x - 3) = 2 \cdot 2x\]
\[7x - 21 = 4x\]
\[7x - 4x = 21\]
\[3x = 21\]
\[x = 21\ :3\]
\[x = 7.\]
\[Ответ:x = 7.\]