SOLUTION: {{{3^(2x+2)-18(3^x)+9=0}}}

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Question 43339: 3%5E%282x%2B2%29-18%283%5Ex%29%2B9=0
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
3^(2x+2)-18(3^x)+9=0
(3^2x)(3^2) -18(3^x) +9=0
Factor out the "9" to get:
3^2x-2(3^x)+1=0
This is a quadratic equation.
Let w=3^x
You get:
w^2-2w+1=0
(w-1)^2=0
Therefore:
(3^x-1)^2=0
3^x=1
x=0
Cheers,
Stan H.