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Math Help - Rearranging log equation

  1. #1
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    Rearranging log equation

    How do I solve this equation for x?

    3log(10)(4x-30)=3 Note: it's log base 10

    I know that the answer is x=10 but have no idea how to get there!

    thx in advance
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  2. #2
    Newbie Phantasma's Avatar
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    Re: Rearranging log equation

    3\log(10)(4x-30)=3\\3(1)(4x-30)=3\\4x=31\\x=\frac{31}{4}
    I think you wrote your equation wrong.
    Thanks from JellyOnion
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  3. #3
    MHF Contributor MarkFL's Avatar
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    Re: Rearranging log equation

    I would first divide through by 3 to get:

    \log(4x-30)=1

    Convert to exponential form:

    4x-30=10^1=10

    Now solve for x.
    Thanks from JellyOnion
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