Question 1116739: Please help me solve this equation: 
How I tried: 2x - (2x+11)/5= (10x-2x+11)/5
So, (10x-2x+11)/5 - (4x-6)/11 = (7-8x)/7 equals (10x-2x+11)/5 times 385(385 is the LCM of the denominators) - (4x-6)/11 times 385 = -(7-8x)/7 times 385, which equals 770x-154x+847-140x-210=-385-440x
Now, Transposition: 770x+440x-154x-140x=-385-847+210 which equals 916x=1442
x=1 526/916
This is the wrong answer; the answer from my key book is 7. I hope you can understand my equation; I've worked it several times and can't get the right answer! I don't think I'm understanding how to work this kind of equation. I appreciate any help you can offer, if you can't understand or get the equation it's ok!
Answer by KMST(5328)   (Show Source):
You can put this solution on YOUR website! I fail to why  is part of your post.
I imagine it is a typo of sorts.
It has nothing to do with
 .
AS you said, the LCM of the denominators is  .
Multiplying both sides of 
times  , we get in more, or less, or different steps
 ,
 ,
 ,
 ,
 ,
 , and  .
There are signs that are wrong in
 ,
but that occasionally happens to the best of us.
It should be
 .
When you see that you get a very ugly fraction,
you have to suspect you made a mistake.
The problem, as I found out in an exam over 50 tears ago,
is to find where you made a mistake.
A sign can mutate as you copy the equation from the bottom of page 1
to the top of page 2, as I remember well.
The solution (in math class, not in life) should be as simple as  ,
which makes  ,  , and  .
You can substitute to get
,
 ,
 ,
 ,
and that makes verifying the solution very simple and easy.
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