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Math Help - Fractions just can't think of what to do here

  1. #1
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    Fractions just can't think of what to do here

    \frac{x}{x+8}=\frac{2}{3}

    The answer is x=16 but I can't see how they're coming to this answer...
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    Re: Fractions just can't think of what to do here

    Quote Originally Posted by uperkurk View Post
    \frac{x}{x+8}=\frac{2}{3}

    The answer is x=16 but I can't see how they're coming to this answer...
    If x\ne -8 then \frac{x}{x+8}=\frac{2}{3} is same as 3x=2x+16.
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    Re: Fractions just can't think of what to do here

    Quote Originally Posted by Plato View Post
    If x\ne -8 then .
    How can I know that x\ne -8? Also can you show me how exactly you got from \frac{x}{x+8}=\frac{2}{3} to 3x=2x+16
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  4. #4
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    Re: Fractions just can't think of what to do here

    The reason for " x\ne -8" is that, in that case, the fraction on the left is not defined.

    And you go from one equation to the other by multiplying both sides by 3(x+ 8), the product of the two denominators.
    Last edited by HallsofIvy; March 26th 2013 at 11:11 AM.
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