Уравнение
2,8-x=7(0,2+0,5)
m-1,2(2-m)=1+2m
8y-9-(4y-5)=1,2y-(4-5y)

1) 2,8-x = 7(0,2+0,5)

2.8-x = 1.4+3.5

-x = 2.1

x = -2.1

2) m-1,2(2-m) = 1+2m

m-2.4+m = 1+2m

0 ≠ 3.4

нет корней

3) 8y-9-(4y-5) = 1,2y-(4-5y)

8y-9-4y+5 = 1.2y-4+5y

4y-4 = 6.2y-4

-2,2y = 0

y = 0

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