Thursday, December 25, 2014

Math question

I saw this math problem some time ago and I was never able to figure the problem out.  Here it is:
\begin{equation}
\frac{3x^2}{9^x} = 27
\end{equation}
I was able to obtain the following steps:
\begin{equation}
\frac{3x^2}{3^{2x}} = 3^3
\end{equation}
\begin{equation}
3x^2 = 3^{2x+3}
\end{equation}
\begin{equation}
x^2 = 3^{2(x+1)}
\end{equation}
This is where I get lost and can't solve it without a CAS or knowing that the answer is -1.  I hope someone can show and explain how to solve it the "pencil and paper" way.

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