1. Do Now In your group, choose someone to fill each role Spokesperson Materials gatherer Writer Scorekeeper Reminders: Tutoring today Turn in benchmark review Friday Turn in Unit 2 Test corrections Friday Ice Cream Party Competition Auction on Friday

3. CPCTC © 2006 by Mr. Mayers CONGRUENCY SHORTCUTS CLASSIFYING TRIANGLES THEOREMS BASICS OF PROOFS TWO COLUMN PROOFS Team 1Team 2Team 3Team 4 0000

4. If ΔABC ≅ ΔDEF, then which angle is congruent to C? Back F

5. Are the triangles congruent? Which shortcut tells you? Back Yes, SAS

6. Classify this triangle by its sides Back Scalene

7. What is the Triangle Sum Theorem? Use it to find the missing angle measure. Back The sum of the angles in any triangle is 180 o, m<C=110 o

8. Back A geometric object is congruent to itself. (AB ≅ AB or <C ≅ <C) What is the reflexive property?

9. Back Which triangle congruency is represented here? SSS

10. What does CPCTC stand for? Back Corresponding Parts of Congruent Triangles are Congruent

11. Given that C is the midpoint of BE and that <A ≅ <D, are the triangles congruent? Which shortcut tells you? Back Yes, AAS

12. Classify this triangle by its angles Back Obtuse

13. Back Do the lengths 9, 6, and 2 form a triangle? No, 6+2 is not greater than 9.

14. Back Vertical Angles are opposite angles from where 2 lines cross. What are vertical angles?

15. Back Which triangle congruency shortcut is represented here? AAS

16. If ΔBCD ≅ ΔFGH, then which side is congruent to GH? Back CD

17. Are the triangles congruent? Which shortcut tells you? Back Yes, AAS

18. Classify this triangle by angles 29 o, 61 o, 90 o Back Right

19. Back State the Base Angle Theorem and use it to find the measure of <Z. If two sides of a triangle are congruent, then the angles opposite those sides are also congruent. 54 o.

20. Back Are these two triangles congruent? Why/ why not?

21. Back Name the two triangles in this diagram that share a reflexive property at angle F.

22. Back BW ≅ MN, OW ≅ AN, or <W ≅ <N Name a non-marked piece of information that is congruent.

23. Are the triangles congruent? Which shortcut tells you? Back No, AAA

24. Back Isosceles (and acute) C is congruent to B and D is congruent to E. What kind of triangles are these?

25. Back What can serve as a counterexample to the conjecture below: “If Miguel wants to prove two triangles are congruent, he must use ASA.” AAS, SSS, SAS, HL

26. Back Name the steps to writing a good two column proof

27. Back Fill in the following chart to complete the two-column proof. Reflexive vertical angle CPCTC AAS

28. In order to prove that CB ≅ ZX, what do we have to prove first? Back ΔCBA ≅ Δ ZXY

29. Are the triangles congruent? Which shortcut tells you? Back No, SSA

30. What is the measure of any interior angle of an equilateral triangle? What do we call this type of triangle? Back 60 o, Equiangular

31. Back 2<x<14 According to the triangle inequality theorem, if 6, 8, and x form a triangle, what are all the possible values for x?

32. Back Write a proof.

33. Back Construct a Two Column Proof