Начнем с открытия скобок:
2 * (0.4x - 1.2) = x + 1.4;
0.8x - 2.4 = x + 1.4;
0.8x - x = 1.4 + 2.4;
-0.2x = 3.8;
x = 3.8 : (-0.2);
x = -19.
Начнем с открытия скобок:
2 * (0.4x - 1.2) = x + 1.4;
0.8x - 2.4 = x + 1.4;
0.8x - x = 1.4 + 2.4;
-0.2x = 3.8;
x = 3.8 : (-0.2);
x = -19.