About Ellipses
An ellipse has the following properties:
• A center point that behaves like the center of a circle. It is a construction entity and can be dimensioned and constrained.
• Two perpendicular radii in any orientation. They are construction entities and can be dimensioned, constrained, and dragged.
If you delete an ellipse's axis, the ellipse is deleted. If you delete the ellipse, the axes and center point are deleted.