Решение:
\[ 7 - 5x - 8 + 4x + 5x + 6 = 25 \]
\[ (-5x + 4x + 5x) + (7 - 8 + 6) = 25 \]
\[ 4x + 5 = 25 \]
\[ 4x = 25 - 5 \]
\[ 4x = 20 \]
\[ x = \frac{20}{4} \]
\[ x = 5 \]
Ответ: $$x = 5$$