2) 8 - (7x + 23) = x - 9 3) (8 - 2x) - (8x + 13) = 0 4) 3(9 - 7x) - 4(-3x + 9) = 17 - 8x 5) (x+8)/6 - (4-x)/4 = (x-11)/2

Решение:

1. Уравнение 2:

\( 8 - (7x + 23) = x - 9 \)

\( 8 - 7x - 23 = x - 9 \)

\( -7x - 15 = x - 9 \)

\( -7x - x = -9 + 15 \)

\( -8x = 6 \)

\( x = \frac{6}{-8} = -\frac{3}{4} \)



2. Уравнение 3:

\( (8 - 2x) - (8x + 13) = 0 \)

\( 8 - 2x - 8x - 13 = 0 \)

\( -10x - 5 = 0 \)

\( -10x = 5 \)

\( x = \frac{5}{-10} = -\frac{1}{2} \)



3. Уравнение 4:

\( 3(9 - 7x) - 4(-3x + 9) = 17 - 8x \)

\( 27 - 21x + 12x - 36 = 17 - 8x \)

\( -9x - 9 = 17 - 8x \)

\( -9x + 8x = 17 + 9 \)

\( -x = 26 \)

\( x = -26 \)



4. Уравнение 5:

\( \frac{x+8}{6} - \frac{4-x}{4} = \frac{x-11}{2} \)

Общий знаменатель равен 12.

\( \frac{2(x+8)}{12} - \frac{3(4-x)}{12} = \frac{6(x-11)}{12} \)

Умножим обе стороны на 12:

\( 2(x+8) - 3(4-x) = 6(x-11) \)

\( 2x + 16 - 12 + 3x = 6x - 66 \)

\( 5x + 4 = 6x - 66 \)

\( 5x - 6x = -66 - 4 \)

\( -x = -70 \)

\( x = 70 \)

Ответ: x = -3/4 (для 2), x = -1/2 (для 3), x = -26 (для 4), x = 70 (для 5).