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Math Help - Logarithmic equation

  1. #1
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    Exclamation Logarithmic equation

    log(base)3 (5x-1)=2 I need help solving this equation. I hope is clear. It's suppose to be log base 3 and 5x-1 is whole term thank you for your attention
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  2. #2
    A Plied Mathematician
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    I would say the first thing to do is raise 3 to both sides of the equation thus:

    \displaystyle{3^{\log_{3}(5x-1)}=3^{2}}.

    Can you see where to go from here?
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  3. #3
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    Unhappy

    I'm sorry I have no idea were to go from there. Do I move the log base 3 (5x-1) up front the 3... like:

    3 log base 3 (5x-1) and then distribute?
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  4. #4
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    if \log_b(a) = c , then b^c = a

    change your log equation to exponential form.
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  5. #5
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    Quote Originally Posted by Ackbeet View Post
    \displaystyle{3^{\log_{3}(5x-1)}=3^{2}}.
    \displaystyle{3^{\log_{3}(5x-1)}=3^{2}}

    \displaystyle{3^{\log_{3}(a) = a}

    Therefore the {3^{\log_{3}} cancels itself out, leaving:

    \displaystyle{(5x-1)=3^{2}}

    You know where to go from here...
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