1. Transformations
What’s it all about?

2. Transformations
A transformation is an operation that moves or changes a geometric figure in some way to produce a new figure. The new figure is called the image. Another name for the original figure is pre-image.
A transformation can be shown using an arrow.
∆ABC  ∆PQR

3. Three main types of transformations:
Translation moves every point of a figure the same distance in the same direction.
Reflection uses a line of reflection to create a mirror image of the original figure.
Rotation turns a figure about a fixed point, called the center of rotation . Rays drawn from the center of rotation to a point and its image form the angle of rotation.

4. Translations
Translation moves every point of a figure the same distance in the same direction.

5. Reflections
Reflection uses a line of reflection to create a mirror image of the original figure.
Reflection video

6. Rotations
Rotation turns a figure about a fixed point, called the center of rotation . Rays drawn from the center of rotation to a point and its image form the angle of rotation.
Rotations of points and shapes
Practice – student computers or iPads

7. Review Practice Show me/Explain Everything
Show me/Explain Everything
Show the difference b/w:
Translations
Reflections
Rotations
Give examples of each one

8. Translations, reflections and rotations are three types of congruence transformations.
A congruence transformation changes the position of the figure without changing its shape and size.
Another name for congruence transformation is isometry.
An isometry is a transformation that preserves length and angle measure.

9. Dilation
A dilation is a transformation that stretches or shrinks a figure to create a similar figure.
Dilatations produce similar figures (not congruent)
In a dilation, a figure is enlarged or reduced with respect to a fixed point called the center of dilation.
Dilatations are enlarged or reduced by a scale factor = the ratio of a side length of the image to the corresponding side length of the original figure.
For example the new figure may be 2x bigger (enlargement)
Or it may be ½ as big (reduction)