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Rotations

  • Rotation: a type of congruence transformation in which an image moves in a circular motion to a new position
  • Center of rotation: the fixed point in which the image is rotating around
  • Methods by which a rotation can be performed:
    • A composite of two successive reflections over two intersecting lines
    • The angle of rotation: the angle formed by the intersecting lines
  • Rotation postulate: in a given rotation, the angle of rotation is twice the measure of the angle formed by the intersecting lines of reflection

Rotations

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Mathematics: Geometry