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3.9+x=
We move all terms to the left:
3.9+x-()=0
We add all the numbers together, and all the variables
x=0
| x*100/126736=122,5 | | 0.7x-3.35=6.4-3.2x | | x*100/126736=115,9 | | 180=3x+83.1 | | 0.3n-21=42/105 | | x*100/144353=104,4 | | x*100/144353=102,3 | | -1/5a=30 | | x*100/67075=92,1 | | x*100/67075=99,3 | | x*100/96385=63 | | —(2k—11)=7 | | x*100/96385=97,4 | | x*100/96385=89,1 | | 8{f-2}=0 | | x*100/28357=105,2 | | x*100/28357=97,4 | | a+3/4=-51/8 | | (6x-2)°=20 | | x*100/29848=99,8 | | 2a+11=6a-33 | | x*100/29848=95,8 | | -4=0,50x | | 40-5c=15 | | 3a=3a+0a | | 40-5c=9 | | 3x+8=4x–4 | | 2⎪x+1⎥-x=3x-4 | | -0.03x^2+6x-3500=0 | | 30+w=6w | | 3d+2d+d=42 | | (8-2x)/2=10 |