SOLUTION: 3/7x +2 =4/7x-5 I have tried this over and over again - i keep coming up with -49, but the answer should be 7. I cannot figure it out. I learned that you should multiply everyth

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Question 95640: 3/7x +2 =4/7x-5
I have tried this over and over again - i keep coming up with -49, but the answer should be 7. I cannot figure it out.
I learned that you should multiply everything by the LCD to make everything a whole number first.

Found 3 solutions by stanbon, edjones, Earlsdon:
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website!
3/7x +2 =4/7x-5
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Since you have posted no parentheses the problem
can be worked in at least 3 ways.
Do you mean?
(3/7)x + 2 = (4/7)x-5
Or
3/(7x+2) = 4/(7x-5)
Or
Some other combination of terms and factors?
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Cheers,
Stan H.

Answer by edjones(8007)   (Show Source):
You can put this solution on YOUR website!

multiply 7 times both sides. 3x+14=4x-35
subtract 4x and 14 from both sides. -x=-49
multiply -1 times both sides x=49
Check:

21+2=28-5
EdJones

Answer by Earlsdon(6294)   (Show Source):
You can put this solution on YOUR website!
I have worked your problem two different ways and find that the answer that you give (x = 7) is just not possible.
In the first place, to remove any ambiguity on the problem statement, please use parentheses! Why? Because...
3/7x can be interpreted to mean either: or
Whereas, (3/7)x can be interpreted only as
In the second place, the only way that I can get the answer that you give, (x = 7) is if the problem starts with , so...
Multiply through by the LCD of 7.
Simplify.
Add 3x to both sides.
Add 35 to both sides.
Finally, divide both sides by 7.
or
Please check the original problem for a possible missing negative sign!