• Selecting the center, a point to locate the major axis, and an angle that rotates the geometry about the major axis.

• Defining the length and orientation of the major axis and specifying the rotation angle about the major axis.

• Locating the center, a point locating the major axis, and a point locating the minor axis.

• Selecting two points to define the major axis, and a third point anywhere else on the ellipse.

• Using a rotation angle about the major axis. The angle represents what you see of a circle after you have rotated it; the more you rotate it, the less you see of it. For example, if you type 0 degrees, the system creates a circle; if you type 90 degrees, it creates a line.