\[(3m - 8) \cdot 4 = 5m - 7\]
\[12m - 32 = 5m - 7\]
\[12m - 5 = 32 - 7\]
\[7m = 25\]
\[m = \frac{25}{7}\]
\[m = 3\frac{4}{7}.\]
\[Ответ:при\ m = 3\frac{4}{7}\text{.\ }\]