\( 2(5 - 2x) - (x + 1) = -6 \)
\( 10 - 4x - x - 1 = -6 \)
\( 9 - 5x = -6 \)
\( -5x = -6 - 9 \)
\( -5x = -15 \)
\( x = \frac{-15}{-5} \)
\( x = 3 \)
Ответ: \(x = 3\).