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Math Help - Exponential Equation

  1. #1
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    Exponential Equation

    3^(3x+5) = 5

    Thgis is precalc review for my calc class... I think I have to take the log of both sides and then the exponent goes out front or something like that but I'm stuck.
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  2. #2
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    3^{3x+5} = 5

    using a^b= c \Rightarrow b = \log_ac

    then

    3x+5 = \log_35

    Can you solve it from here?
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  3. #3
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    Yes, but only with a calculator and converting to decimals. I don't really have the theory down.
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  4. #4
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    Quote Originally Posted by katekate View Post
    3^(3x+5) = 5

    Thgis is precalc review for my calc class... I think I have to take the log of both sides and then the exponent goes out front or something like that but I'm stuck.
    \ln(3^{3x+5}) = \ln(5)

    (3x+5)\ln(3) = \ln(5)

    3x+5 = \frac{\ln(5)}{\ln(3)}

    can you finish now?
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  5. #5
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    yeah but with decimals again if that makes a difference.
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