а) 0,4х = -6 x = -15 б) x + 6 = 5 + 4x x - 4x = 5 - 6 -3x = -1 x = 1/3 в) 13 - 3x - 3 = 4 - 5x -3x + 5x = 4 + 3 - 13 2x = -6 x = -3 г) 0.6x - 1 -0.3x +0.3 = -0.7 0.6x -0.3x = -0.7 +0.3x + 1 0.3x = 0.6x x = 2