Counting Rectangles
Source:
March 23, 2008
geometryrectangle
Problem Statement
Determine the number of non-degenerate rectangles whose edges lie completely on the grid lines of the following figure.
\begin{tabular}{|c|c|c|c|c|c|} \hline & & & & & \\
\hline & & & & & \\
\hline & & \multicolumn{1}{c}{} & & & \\
\cline{1 \minus{} 2}\cline{5 \minus{} 6} & & \multicolumn{1}{c}{} & & & \\
\hline & & & & & \\
\hline & & & & & \\
\hline \end{tabular}