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Thread: solving for x.

  1. #1
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    solving for x.

    Solve for x
    2x/(x-3)=4+(6/(x-3)
    2x=4+6
    2x=10
    x=5

    But if I put 5 in for x in the equation it doesnt work.

    Where am I going wrong?
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  2. #2
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    You cannot cancel the (x-3)'s as you did.

    Take this case which is similar:
    20/4 = 2 + 12/4
    You can plainly see that 20 is not equal 2 + 12, right?
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  3. #3
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    yes
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  4. #4
    Super Member 11rdc11's Avatar
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    You are getting confused there is no solution for this problem.
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  5. #5
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    20/4 = 2 + 12/4

    If we change the 2 to 8/4, then:
    20/4 = 8/4 + 12/4
    20 = 8 + 12
    Clear?

    Work your problem the same way.
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  6. #6
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    alright! thanks.
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  7. #7
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    Quote Originally Posted by 11rdc11 View Post
    You are getting confused there is no solution for this problem.
    True; but I think his equation: 2x/(x-3)=4+(6/(x-3)
    should be:
    2x/(x-3) = 4 + 6x/(x-3)
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  8. #8
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    well its 6 over x-3
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  9. #9
    Super Member 11rdc11's Avatar
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    Quote Originally Posted by dtownangel View Post
    well its 6 over x-3

    Like this?

    \frac{2x}{x-3} = 4 + \frac{6}{x-3}
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  10. #10
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    yeah

    does x=-3
    Last edited by mr fantastic; Sep 11th 2009 at 07:50 PM. Reason: Merged posts
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  11. #11
    Super Member 11rdc11's Avatar
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    Quote Originally Posted by dtownangel View Post
    yeah
    K then the problem has no solution. When you work it out you end up with x= 3 which can't be because you would be dividing by zero which is not allowed
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  12. #12
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    No; you should get x = 3.
    Which means "no solution", since x - 3 = 0; division by 0 is illegal.
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