Решить уравнение (подробно)

2 * (x+2.5) - 4 * (1.5-1) = - 3

3 * (1.6x-0.2) - 2 * (0.6x+2.5) = x+2.2

1.8 * (5-2x) - 2 * (0.8x+2.5) = 8-1.2x

2 * (x+2.5) - 4 * (1.5-1) = - 3

2x+5-6+4=-3

2x=-3-5+6-4

2x=-6

x=-6/2

x=-3

Проверка: 2 * (-3+2.5) - 4 * (1.5-1) = - 3

2*-0.5-4*0.5=-3

-1-2=-3

-3=-3

3 * (1.6x-0.2) - 2 * (0.6x+2.5) = x+2.2

4.8x-0.6-1.2x-5=x+2.2

4.8x-1.2x-x=2.2+0.6+5

2.6x=7.8

x=7.8/2.6

x=3

Проверка: 3 * (1.6*3-0.2) - 2 * (0.6*3+2.5) = 3+2.2

3*4.6-2*4.3=5.2

13.8-8.6=5.2

5.2=5.2

1.8 * (5-2x) - 2 * (0.8x+2.5) = 8-1.2x

9-3.6x-1.6x-5=8-1.2x

-3.6x-1.6x+1.2x=8-9+5

-4x=4

x=4/-4

x=-1

Проверка: 1.8 * (5-2 * (-1)) - 2 * (0.8 * (-1) + 2.5) = 8-1.2 * (-1)

1.8*7-2*1.7=8+1.2

12.6-3.4=9.2

9.2=9.2