1330):
2) - 4x + 8 - 7 = x - 1;
4) 5y = 2y + 9.
2) 5(y + 3) = 10;
4) 6(z - 1) = 18. ​

1) -4х+8-7 = х-1

-4х-х = -1-8+7

-5х = -9+7

-5х = 2

х = -2/5

2) 5у = 2у+9

5у-2у = 9

3у = 9

у = 9:3

у = 3

3) 5(у+3) = 10

у+3 = 10:5

у+3 = 2

у = 2-3

у = -1

4) 6(z-1) = 18

z-1 = 18:6

z-1 = 3

z = 3+1

z = 4

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