1. MOTION IN GEOMETRY: TRANSFORMATIONS
1.6
Geometry

2. CONGRUENCE
Figures that match exactly (SHAPE & SIZE) are said to be congruent

3. TRANSFORMATIONS RIGID TRANSFORMATIONS
The movement of a figure in a plane from its original position, the preimage, to a new position, the image.
RIGID TRANSFORMATIONS
Transformations that do not change the size or shape of a figure.

4. Transformations Preimage Image The figure before you move it.
Usually named with letters
Example: A, B, AB…
Image
The figure after it has been moved
Usually named with a letter and a prime symbol (apostrophe)
Example: A’, B’, A’B’…

5. 3 Main Types of Transformations
TRANSLATIONS
ROTATIONS
REFLECTIONS

6. TRANSLATIONS
Every point of a figure moves in a straight line, and all points move the same distance and in the same direction.

7. EXAMPLES

8. ACTIVITY 1
Translating an image

9. ROTATIONS
Every point of a figure moves around a given point known as the center of rotation. All points move the same angle measure.

10. EXAMPLES

11. EXAMPLES

12. ACTIVITY 2
Rotating an image

13. REFLECTIONS
A line plays the role of a mirror, and every point in a geometric figure is “flipped” across the line.

15. EXAMPLES

16. EXAMPLES

17. ACTIVITY 3, PART 1
The Reflection of a Point

18. If a point is reflected across a line, then the line is the ______________ ____________ of the segment that connects the point with its image.

19. ACTIVITY 3, PART 2
The Reflection of a Triangle

20. If a triangle is reflected across a line, then the reflected image of the triangle is ____________ to the original triangle

21. Glide Reflection

22. Glide Reflection
A combination of a translation and a reflection.