2-(0,9x-1.3)=1.3x
2-0,9x+1.3=1.3x
-0.9x-1.3x=-2-1.3
-2.2x=-3.3
x=1.5
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-(3.3x+1.2)-(0.7x+1.6)=0
-3.3x-1.2-0.7x-1.6=0
-3.3x-0.7x=1.2+1.6
-4x=2.8
x=-0.7
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-(4.1x+2.5)-(2.3x+3.9)=1.6
-4.1x-2.5-2.3x-3.9=1.6
-4.1x-2.3x=2.5+3.9
-6.4x=6.4
x=-1
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(3.6x+2.5)-(1.8x+2.3)=1.6x
3.6x+2.5-1.8x-2.3=1.6x
3.6x-1.8x-1.6x=2.3-2.5
0.2x=-0.2
x=-1