12. Реши: 4(х-2) = 20; 6.(х-3) = 42; 7.(х-5) = 35. Ответ:

Решение:

Решаем каждое уравнение отдельно:

1. \( 4(x - 2) = 20 \)
   \( x - 2 = \frac{20}{4} \)
   \( x - 2 = 5 \)
   \( x = 5 + 2 \)
   \( x = 7 \)
2. \( 6(x - 3) = 42 \)
   \( x - 3 = \frac{42}{6} \)
   \( x - 3 = 7 \)
   \( x = 7 + 3 \)
   \( x = 10 \)
3. \( 7(x - 5) = 35 \)
   \( x - 5 = \frac{35}{7} \)
   \( x - 5 = 5 \)
   \( x = 5 + 5 \)
   \( x = 10 \)

Ответ: x = 7, x = 10, x = 10.