`3,2.x+(-1.2).x+2.7= -4.9`

`3,2*x + (-1,2)*x = -7,6`

`x*(3,2 - 1,2) = -7,6`

`x * 2 = -7,6`

`x = -3,8`

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` (-5.6).x+2.9.x-3.86= -9.8`

`-5,6*x + 2,9*x = -5,94`

`x*(-5,6 + 2,9) = -5,94`

`x * (-2,7) = -5,94`

`x = 2,2`