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0.4x+3.9=578
We move all terms to the left:
0.4x+3.9-(578)=0
We add all the numbers together, and all the variables
0.4x-574.1=0
We move all terms containing x to the left, all other terms to the right
0.4x=574.1
x=574.1/0.4
x=1435+0.10000000000002/0.4
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