ВАРИАНТ 7 1. 12x-5 = 7x + 10 2. 4(3x + 5) - 6x = 2

Решение:

1. \(12x - 5 = 7x + 10\)
   \(12x - 7x = 10 + 5\)
   \(5x = 15\)
   \(x = 3\)
2. \(4(3x + 5) - 6x = 2\)
   \(12x + 20 - 6x = 2\)
   \(6x + 20 = 2\)
   \(6x = 2 - 20\)
   \(6x = -18\)
   \(x = -3\)

Ответ: 1. x=3; 2. x=-3.