Posted by **lindsay** on Thursday, July 19, 2012 at 10:16am.

Solve the equation

3^2x - 12 x 3^x + 27 = 0

- math -
**Reiny**, Thursday, July 19, 2012 at 3:04pm
let 3^x = y

so we get

y^2 - 12y + 27 = 0

(y-3)(y-9) = 0

y = 3 or y = 9

then

x^2 = 3 or x^2 = 9

x = ± √3 or x = ± 3

btw, in something like 12 x 3^x , do not use x as a multiplication sign, especially if you have a variable x

either say just 12(3^x) or say 12*3^x

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