Question 339533
following your step
multiply by the LCD,12. to get rid of the fractions
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you did
24x+12/3 - 36-12x/4 = 12x/6

you are not clear with how you are multiplying both sides 
(24x+12)/3 -(36-12x)/4=12x/6  
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which yiels
8x+4-9+3x=2x   you got 8x+4-9-3x=2x  you have missed distributing the negative to -12x

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by the way, it is much easier to do the following, after you multiply the LCD
12(2x+1)/3-12(3-x)/4=12x/6
after this step, simply the ratios
4(2x+1)-3(3-x)=2x