Решите уравнение: a) 10-3 (5x-1,5) = 2,5-5x б) 2 (3x-4) = 5x-3 (x+1)

a) Найдем х.

10 - 3 * (5 * x - 1,5) = 2,5 - 5 * x;

Скобки раскроем.

10 - 3 * 5 * x + 3 * 1.5 = 2.5 - 5 * x;

10 - 15 * x + 4.5 = 2.5 - 5 * x;

Приведем к виду a * x = b.

-15 * x + 5 * x = 2,5 - 10 - 4,5;

-10 * x = 2 - 10 - 4;

-10 * x = - 8 - 4;

-10 * x = - 12;

10 * x = 12;

x = 12/10;

x = 1.2.

б) 2 * (3 * x - 4) = 5 * x - 3 * (x + 1);

2 * 3 * x - 2 * 4 = 5 * x - 3 * x - 3;

6 * x - 8 = 5 * x - 3 * x - 3;

6 * x - 8 = 2 * x - 3;

6 * x - 2 * x = - 3 + 8;

4 * x = 5;

x = 5/4;

x = 1.25.