2 Задача: Решите уравнение. a) -3(-x+4) = 2x - 5 г) -6(3x + 1) - 4 = -22 6) n - 12 = (n + 3)(-4) д) -3, 5у + 5,6 = 4(1, 8y + 2, 4) в) 23 - 5(m + 8) = 48 e) -4(0, 7y - 2,5) = -3y + 9,5

Решение:

1. а) -3(-x + 4) = 2x - 5
   \( 3x - 12 = 2x - 5 \)
   \( 3x - 2x = 12 - 5 \)
   \( x = 7 \)
2. б) n - 12 = (n + 3)(-4)
   \( n - 12 = -4n - 12 \)
   \( n + 4n = 12 - 12 \)
   \( 5n = 0 \)
   \( n = 0 \)
3. в) 23 - 5(m + 8) = 48
   \( 23 - 5m - 40 = 48 \)
   \( -5m - 17 = 48 \)
   \( -5m = 48 + 17 \)
   \( -5m = 65 \)
   \( m = \frac{65}{-5} \)
   \( m = -13 \)
4. г) -6(3x + 1) - 4 = -22
   \( -18x - 6 - 4 = -22 \)
   \( -18x - 10 = -22 \)
   \( -18x = -22 + 10 \)
   \( -18x = -12 \)
   \( x = \frac{-12}{-18} \)
   \( x = \frac{2}{3} \)
5. д) -3, 5y + 5,6 = 4(1, 8y + 2, 4)
   \( -3.5y + 5.6 = 7.2y + 9.6 \)
   \( 5.6 - 9.6 = 7.2y + 3.5y \)
   \( -4 = 10.7y \)
   \( y = \frac{-4}{10.7} \)
   \( y = -\frac{40}{107} \)
6. е) -4(0, 7y - 2,5) = -3y + 9,5
   \( -2.8y + 10 = -3y + 9.5 \)
   \( -2.8y + 3y = 9.5 - 10 \)
   \( 0.2y = -0.5 \)
   \( y = \frac{-0.5}{0.2} \)
   \( y = -2.5 \)

Ответ: а) x = 7; б) n = 0; в) m = -13; г) x = 2/3; д) y = -40/107; е) y = -2.5.