Ellipses
Symmetry
Ellipses have both reflectional and rotational symmetry. The reflectional symmetry of every ellipse is a vertical line through the center and a horizontal line through the center. The rotational symmetry of every ellipse is 180 degrees about the center point.
Example State the symmetry for the ellipse modeled by the equation:
Example State the symmetry for the ellipse modeled by the equation:
Step 1. State the center.
The center of the ellipse is (-2, 5)
Step 2. State the reflectional symmetry.
This ellipse has lines of symmetry at x = -2 and y = 5.
Step 3. State the rotational symmetry.
This ellipse has 180 degree rotational symmetry about (-2, 5).