# Isoperimetric
Parallelograms

The applet below displays a parallelogram
with fixed perimeter. Drag points C or D and observe the trace that
results on the graph. You may also use the **Animate** buttons to
observe similar results. To clear the trace, click on the red X in
the lower right-hand corner. The trace provides a visual of the
relationship between side AC and the area of the parallelogram ACDE;
that is, the plot represents the area of the parallelogram as a
function of side AC. Describe this relationship.