1. Space and Shapes Unit GRADE 9 MATH

2. True Translations, Reflections and 180 Degree Rotations E2 MAKE AND APPLY INFORMAL DEDUCTIONS ABOUT THE MINIMUM SUFFICIENT CONDITIONS TO GUARANTEE A TRANSLATION, REFLECTION AND A 180 DEGREE ROTATION

3. What to review for this lesson… 1.What do different transformations look like: translation, reflections and rotations? 2.What have we learned about the minimum conditions for different transformations? 1.Translation: line segments that join corresponding points are parallel and congruent 2.180 Rotation: the line segments that join matching verticies, intersect each other at a common midpoint 3.Reflection: the line segments that join matching points have common, perpendicular bisector 4.**Note: there are others… 3.What do we know already about mapping rule characteristics for each transformation?

4. Activity #1 1.For the 2 images on the right, what transformations could be happening in each one? (you may relabel the vertices if it proves your point) 2.How do you know? 3.What characteristics of transformations can you use to prove that it is true? (parallel lines, congruent line segments, perpendicular lines)

5. Activity #1 The first diagram has ____________ ____________ 1.____________ 2.____________ 3.____________ Based on this evidence we have a 180 degree rotation

6. Activity #1 The second diagram is not as clear because the pre-image and image are overlapping. ____________ 1.____________ 2.____________ Based on this evidence we have a 180 degree rotation

7. Activity #2 Working with a partner, decide what kind of translations have been represented in each diagram. Make a list of what you would need to prove in order to prove that these transformations are true.

8. Activity #3 10 questions 1.Students will work in groups of 4. You will be given a set of cards. 2.Students will take turns being the host. Only the host can look at the info side of the card 3.The rest of the group needs to ask questions to determine what kind of transformation has taken place 4.Groups may only ask the host 10 questions.

9. Practice Question Use the image to the right to answer the following question. Ms M. Athteacher told Stu Dent that if he was to do a reflection across the line RC, point A would map onto point B. Stu did not think this was correct because BM is not given equal length as AM. Use what you know about properties of triangles and transformations to explain in a short paragraph why Ms M. Athteacher is correct.