Point Symmetry
A geometric transformation, characterized by a fixed point C, called the centre of symmetry, that maps every point P of the plane or space to a point P’ such that point C is the midpoint of segment PP’.
Property
Point symmetry is a dilation with a ratio of –1. Therefore, the centre of the dilation is the centre of symmetry of the initial figure and its image, and the centre of the point symmetry.Examples
A square, a circle and an ellipse are symmetric about a point C. Therefore, each of these figures may be mapped to itself by a point symmetry.
