0,4x + (-x-1,8) = -2 (0,5x-3) решите

Найдем корень уравнения.

0,4 * x + (-x - 1,8) = - 2 * (0,5 * x - 3);

Раскроем скобки.

0.4 * x - x - 1.8 = - 2 * 0.5 * x - 2 * (-3);

0.4 * x - x - 1.8 = - 1 * x + 2 * 3;

x * (0.4 - 1) - 1.8 = - x + 6;

x * (-0.6) - 1.8 = - x + 6;

-0.6 * x - 1.8 = - x + 6;

-0.6 * x + x = 6 + 1.8;

x * (-0.6 + 1) = 7.8;

x * (-0.4) = 7.8;

-0.4 * x = 7.8;

x = - 7.8/0.4;

x = - 78/4;

x = - 39/2;

x = - 19.5;

Ответ: х = - 19,5.