Решение:
- \( 2x + 5 = 2(-x + 1) + 11 \)
\( 2x + 5 = -2x + 2 + 11 \)
\( 2x + 5 = -2x + 13 \)
\( 2x + 2x = 13 - 5 \)
\( 4x = 8 \)
\( x = \frac{8}{4} \)
\( x = 2 \) - \( 6y - 3(y - 1) = 4 + 5y \)
\( 6y - 3y + 3 = 4 + 5y \)
\( 3y + 3 = 4 + 5y \)
\( 3 - 4 = 5y - 3y \)
\( -1 = 2y \)
\( y = -\frac{1}{2} \) - \( 4(x - 1) - 3 = -(x + 7) + 8 \)
\( 4x - 4 - 3 = -x - 7 + 8 \)
\( 4x - 7 = -x + 1 \)
\( 4x + x = 1 + 7 \)
\( 5x = 8 \)
\( x = \frac{8}{5} \) - \( -2(5x - 9) + 2 = 15 + 7(-x + 2) \)
\( -10x + 18 + 2 = 15 - 7x + 14 \)
\( -10x + 20 = 29 - 7x \)
\( 20 - 29 = -7x + 10x \)
\( -9 = 3x \)
\( x = -3 \) - \( 12 + 4(x - 3) - 2x = (5 - 3x) + 9 \)
\( 12 + 4x - 12 - 2x = 5 - 3x + 9 \)
\( 2x = 14 - 3x \)
\( 2x + 3x = 14 \)
\( 5x = 14 \)
\( x = \frac{14}{5} \)
Ответ: 1. \( x = 2 \); 2. \( y = -\frac{1}{2} \); 3. \( x = \frac{8}{5} \); 4. \( x = -3 \); 5. \( x = \frac{14}{5} \).