\[ -2x + 4(x - 1) = 8 \]
\[ -2x + 4x - 4 = 8 \]
\[ (-2x + 4x) - 4 = 8 \]
\[ 2x - 4 = 8 \]
\[ 2x = 8 + 4 \]
\[ 2x = 12 \]
\[ x = \frac{12}{2} \]
\[ x = 6 \]
Проверка:
\[ -2(6) + 4(6 - 1) = -12 + 4(5) = -12 + 20 = 8 \]
Ответ: 6