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Indicial Equations Help

  1. Mar 13, 2009 #1
    1. The problem statement, all variables and given/known data
    I'm just confused about a few little indicial equations.

    1. 3^2x-36X3^x=-243
    2.5(x+2)^2=80


    3. The attempt at a solution
    1.3^2x X 3^x=-207


    2.5(x^2+4x+4)=80
    5x^2+20x+20=80
    5x^2+20x=60

    Unsure what to do after both of them.
     
  2. jcsd
  3. Mar 13, 2009 #2

    rock.freak667

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    Homework Helper

    For the first one....realize that 32x=(3x)2 and then put y=3x

    For the second one, even though you didn't really need to square out and expand, just factorize it. But since 5 is a common factor, divide by 5 first.
     
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