This is the step-by-step, printable version. If you PRINT this page, any ads will not be printed.
See also the animated version.
|After doing this||Your work should look like this|
|Start with a given ellipse with its major and minor axes shown.|
|1. With the compasses' point on the center, set the compasses' width to half the width (major axis) of the ellipse.|
|2. Move the compasses' point to one end of the minor axis of the ellipse and draw two arcs across the major axis.|
|3. Where these arcs cross the major axis are the foci of the ellipse. Label them F1, F2.|
|4. Done. The two points F1, F2, define the foci of the ellipse.|