1. A figure has vertices A(2,2), B(6,4), C(-2,3), and D(-1, 5)
A figure has vertices A(2,2), B(6,4), C(-2,3), and D(-1, 5). The image of this figure is a rotation 180° What is A’? 2. What is B’? 3. What is C’? 4. What is D’?
Bell Ringer

2. Announcement Your test will be on THURSDAY, Nov 20. It will cover:
Section 1.4 “Ordered Pairs and Relations”
Section 2.6 “Graphing in Four Quadrants”
Section 2.7 “Translations and Reflections”
Section 6.8 “Dilations”
Section 11.3 “Rotations”
Lesson 8: “Congruence and Transformations”
You will have a laptop check on FRIDAY, Nov.21

3. Transformations Graphic Organizer
Transformations: An operation that maps an original geometric figure onto a new figure
Translations: When you SLIDE a figure from one position to another without turning it
Reflections: When you FLIP a figure over a line
Rotations: Transformation in which a figure is turned around a fixed point
Dilations: A transformation that enlarges or reduces a figure by a scale factor

4. EXAMPLES Translations Reflections
3 units to the left and 4 units up
ORIGINAL NEW
reflection over the x-axis ORIGINAL NEW

5. EXAMPLES Rotations Dilations Rotate 90° clockwise ORIGINAL NEW
Scale factor of ½ ORIGINAL NEW

6. Lesson 8 Congruence and Transformations
R drive > Key > Week 15 > Monday > Lesson 8 PowerPoint File > Save As > P drive > Math > Week 15 > Lesson 8 PowerPoint

7. VOCABULARY
Congruent Figures – Figures that have the same size and shape
Similar Figures – Figures that are the same shape, but not necessarily the same size

8. QUESTION TO PONDER
Which transformations can we use to show that 2 figures are congruent?
What transformations can we use to show that 2 figures are similar?

9. Go to www.nctm.org/coremathtools
Click on downloadable suite in the top paragraph.
A box will appear that says, “What should Firefox do with this file?” The OPEN WITH circle will be selected. Click OK at the bottom of the box.
Another box will open, click RUN.
When you see this blue box appear, click on the middle option in the bottom row, called Coordinate.
Wait for further instructions.

10. What Have We Noticed?
We can translate, reflect, and rotate to determine if figures are congruent. Figures that have been translated, reflected, or rotated have the same shape and are the same size.