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Quick question, say I'm simplying a solution I got using the quadratic equation and I run into this:

Original version (as posted by OP):

x = -7 +- 3 sqrt(5) over 3

Edited version: $$ x = \frac{-7\pm 3 \sqrt{5} }{3} $$ Would the two $3$s cross each out leaving the answer to be $x = -7 \pm \sqrt{5}$, or is that illegal in terms of rules and you have to simplify all the terms, including the $-7$ if you were to simplify correctly.

Thanks!

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    $\frac{a\pm b}{3} = \frac a 3 \pm \frac b 3$2011-12-06
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    Does my eq. edit correspond to what you wanted to ask?2011-12-06
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    @percusse: your edit makes Gerry's first sentence (and indeed the whole answer) look rather silly. Please do not edit in such ambiguous cases but rather suggest your interpretation in a comment.2011-12-06
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    @t.b. It says quadratic equation so it doesn't take too much to guess what OP means, that's why I asked him (it doesn't take too much effort to rollback anyway). And I don't think any edit can make Gerry's arguments silly.2011-12-06
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    @percusse: Unfortunately you've removed the opportunity for us to impress on OP the importance of parentheses...2011-12-06
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    @percusse: What is ambiguous now?2011-12-06
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    @J.M. I don't get it. There is not even a question posed properly but Gerry is progressively answering and question reads well after the edit. I don't see what the problem is.2011-12-06
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    @t.b. Maybe it's a premature answer, before resolving the ambiguity ?2011-12-06
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    "There is not even a question posed properly" - sorta kinda the point of Gerry explaining parentheses in the comments to his answer... oh well; I like Martin's take.2011-12-06
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    I'm very confused, I thought the question now has two forms of it and it is understandable. Can I cross out those 3s or not? Thanks everyone.2011-12-06
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    @user1062058 Just tell us if you meant the version indicated by **edited version** or not. Then, as you can see people are in the line waiting to help you.2011-12-06
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    the edited version is what I'm talking about. Thanks.2011-12-06
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    @user1062058 Then $7$ gets divided also. But I am sure that the details would be filled up soon in the answer. You have to be careful about these things as you can see, it is super ambiguous if you don't follow a few basic notational hierarchy.2011-12-06
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    Can you show me how the final answer would look then? Thanks.2011-12-06

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