Nine-point conic

This example demonstrates how a FreeConic can be used to describe an arbitrary conic section by setting its matrix in some script.

The conic in question here is the nine point conic (green): for four points A through D (red) it passes through the pairwise midpoints (cyan) and also through the intersections (yellow) of opposite lines (blue). Furthermore, it is the locus of the center for any conic passing through these four (magenta). See this Math Stack Exchange post for details.