whats solution to (3)^2x-36(3)^x+243=0

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- Apr 27th 2012, 11:39 AMkukid13how to solve this exponential equation?
whats solution to (3)^2x-36(3)^x+243=0

- Apr 27th 2012, 11:49 AMa tutorRe: how to solve this exponential equation?
$\displaystyle (3^x)^2-36(3^x)+243=0$

Substitute $\displaystyle y=3^x$ if you like. Factorise. - Apr 27th 2012, 11:51 AMkukid13Re: how to solve this exponential equation?
then you just use quadratic formula?

- Apr 27th 2012, 11:54 AMa tutorRe: how to solve this exponential equation?
That will certainly work.

- Apr 27th 2012, 12:01 PMkukid13Re: how to solve this exponential equation?
your solution set is 9, -27, but when i try testing them with original equation im not getting right answer, is there something im missing

- Apr 27th 2012, 12:34 PMskeeterRe: how to solve this exponential equation?
- Apr 27th 2012, 12:45 PMkukid13Re: how to solve this exponential equation?
but when i try to plug those back into equation im coming up with funky answers? what am i missing

- Apr 27th 2012, 12:50 PMskeeterRe: how to solve this exponential equation?