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Math Help - Exponential Equations

  1. #1
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    Exponential Equations

    Solve

    4^2x=2^5-x
    and
    9^x+1=27^2x-3

    For the first one I keep getting like .4, and forthe life of me I can not figure out what im not doing right.
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  2. #2
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    e^(i*pi)'s Avatar
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    I assume you mean 4^{2x} = 2^{5-x}

    Note that 4^{2x} = 2^{4x}

    Now if two bases are equal then their exponents must also be equal so you get the linear equation 4x = 5-x which is easy to solve


    For question 2 use the fact that 9 = 3^2 \text{  and  } 27 = 3^3
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  3. #3
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    Thank you!
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