9-39-3RotationsRotationsObjectiveObjective::

To draw and identify rotation images of figuresTo draw and identify rotation images of figures

Transformation TermsTransformation: Moving a geometric figure

Rigid Transformation or Isometry: congruent figuresNon Rigid Transformation: figures not congruent

Notation:Preimage: Image [new figure]:

Translation: Image slides.All points of figure slide along a parallel path.

Rotation: All points rotate or turn around a point.

Reflection: Produces the “mirror” image across a line- line of reflection

ABC - Original CBA - Image1st CBA - Image 2nd

Preimage Image Describe how to move from the preimage to the image.

slide

rotate

Rotational SymmetryRotational Symmetry:

Rotated image coincides with originaln-fold rotational symmetry

900 1800 2700

4-fold rotational symmetry

3600

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