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More LaTeX practice related to the video at http://www.khanacademy.org/math/algebra/solving-linear-equations/v/simple-equations 

\begin{eqnarray*}
7x & = & 14 \\
7 \times x & = & 14 \\
\frac{7x}{7} & = & \frac{14}{7} \\
x & = & 2
\end{eqnarray*}

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