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I'm having trouble solving the following equation

$$2^{2x}+2^x-12=0$$

I think maybe I'm suppose to take $\log_2$ perhaps.... not seeing anything poping out.

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    $\begingroup$ Write $2^{2x}$ as $(2^x)^2$. Do you see a quadratic equation? $\endgroup$ – imranfat Dec 3 '16 at 3:54
  • $\begingroup$ $2^{2x}+2^x-12=(2^x+4)(2^x-3)$. $\endgroup$ – Michael Hoppe Dec 3 '16 at 12:01
  • $\begingroup$ Why was this downvoted? $\endgroup$ – Clclstdnt Dec 4 '16 at 18:02
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$$\begin{align} & (2^x)^2 + 2^x - 12 = 0 \\[10pt] & u^2+u-12 = 0 \end{align}$$ Solve for $u$, then figure out what $x$ is if $u = 2^x$. Recall that $2^x$ must be positive, so discard any negative values of $u$.

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  • $\begingroup$ duh. Forgot that. Thanks $\endgroup$ – Clclstdnt Dec 3 '16 at 3:59

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