Ответ:

9 и 4/7

Объяснение:

1.2 * (X – 3) + 0.4 * (1 – X) = 4

1.2X – 3.6 + 0.4 – 0.4X = 4

0.8X – 3.2 = 4

0.8X = 7.2

X = 9

(2 – 3X)/4 + (1 – X)/2 = (4 – 3X)/8

Умножим обе части уравнения на 8:

2 * (2 – 3X) + 4 * (1 – X) = 4 – 3X

4 – 6X + 4 – 4X = 4 – 3X

–10X + 4 = –3X

–7X = –4

7X = 4

X = 4/7

Объяснение:

1,2(х-3)+0,4(1-х)=4

1,2х-3,6+0,4-0,4х=4

1,2х-0,4х=4+3,6-0,4

0,8х=7,2;  х=9

(2-3х)/4 + (1-х)/2 = (4-3х)/8

2(2-3х) + 4(1-х) = 4-3х

4-6х+4-4х=4-3х

3х-6х-4х=4-4-4

-7х=-4; х=4/7