Two-Column Proof Example

              
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\usepackage{TwoColumnProof}

\title{Two-Column Proof Example}

%% Using example from http://www.sparknotes.com/math/geometry3/geometricproofs/section1.rhtml

\begin{document}

\includegraphics[width=.3\textwidth]{sampleproof}

\section*{Given:}
\begin{itemize}
\item Segment AD bisects segment $BC$.
\item Segment BC bisects segment $AD$. 
\end{itemize}

\section*{Prove:}
\begin{itemize}
\item $\triangle ABM$ and $\triangle DCM$ are congruent. 
\end{itemize}

\begin{TwoColumnProof}
\StatementReason{Segment $AD$ bisects segment $BC$.}
{Given.}

\StatementReason{Segments $AM$ and $MD$ are congruent. \label{label1}}
{When a segment is bisected, the two resulting segments are congruent.}

\StatementReason{Segment $BC$ bisects segment $AD$.}
{Given.}

\StatementReason{Segments $BM$ and $CM$ are congruent.}
{When a segment is bisected, the two resulting segments are congruent.}

\StatementReason{$\angle AMB$ and $\angle DMC$ are congruent.}
{Verticle angles are congruent.}

\StatementReason{$\triangle ABM$ and $\triangle DCM$ are congruent.}
{SAS postulate (2, 4, 5).}
\end{TwoColumnProof}

\end{document}