4 important congruence postulates:

1. Geometry Section 4-2BCongruent TrianglesPg. 260 – you will need a protractor and a ruler (cm).Be ready to grade 4-2A

2. 4 important congruence postulates: S-S-S side-side-side If each of the 3 sides of one triangle are congruent to the sides of another triangle, then the two triangles are congruent. http://www.mathopenref.com/congruentsss.html

3. 4 important congruence postulates: S-A-S side-angle-side If two sides and the included angle of one triangle are congruent to two sides and the included angle of another triangle, then the two triangles are congruent. http://www.mathopenref.com/congruentsas.html

4. 4 important congruence postulates: A-S-A angle-side-angle If two angles and the included side of one triangle are congruent to two angles and the included side of another triangle, then the two triangles are congruent. http://www.mathopenref.com/congruentasa.html

5. 4 important congruence postulates: S-A-A side-angle-angle If two angles and a side opposite oneof them in one triangle are congruent to the corresponding parts of another triangle, then the two triangles are congruent. http://www.mathopenref.com/congruentaas.html

6. 2 postulates that DO NOT work: angle-angle-angle http://www.mathopenref.com/congruentaaa.html angle-side-side http://www.mathopenref.com/congruentssa.html 6

7. If possible, write a congruence statement for each pair of triangles. Name the triangle congruence postulate that applies. If they are not congruent, say so. Try It: pg. 263 a. b. rABC may be @rOMN. More info needed. rDEF @rRQP. SAA Postulate.

8. Exercises Name the side opposite ÐMPN. MN #1pg. 263

9. Exercises Name the angle opposite QN. ÐQMN #2pg. 263

10. Exercises Name the included side for ÐQMP andÐQPM. MP #3pg. 263

11. Exercises Name the included angle for QP and PM. ÐQPM #4pg. 263

12. Exercises If possible, write a congruence statement for each pair of triangles. Name the triangle congruence postulate that applies. If they are not congruent, say so. #5pg. 263 rABC @rFDE SSS Postulate.

13. Exercises If possible, write a congruence statement for each pair of triangles. Name the triangle congruence postulate that applies. If they are not congruent, say so. #6pg. 263 rRST @rYXZ SAS Postulate.

14. Exercises If possible, write a congruence statement for each pair of triangles. Name the triangle congruence postulate that applies. If they are not congruent, say so. #7pg. 264 rPQR @rKJH SAS Postulate.

15. Exercises If possible, write a congruence statement for each pair of triangles. Name the triangle congruence postulate that applies. If they are not congruent, say so. #8pg. 264 rABC @rDEC SAS Postulate. (Vertical angles are congruent.)

16. Exercises If possible, write a congruence statement for each pair of triangles. Name the triangle congruence postulate that applies. If they are not congruent, say so. #9pg. 264 rRSU @rTUS SSS Postulate.

17. Let’s Practice – Which Postulate? SSS SAS

18. Let’s Practice – Which Postulate? SAA SAA

19. Let’s Practice – Which Postulate? Not necessarily congruent ASA

20. Let’s Practice – Which Postulate? SAA

21. a) SAS b) none c) none d) SAA e) SSS f) SAS g) SAS h) SAA i) none

22. Homework: Practice 4-2B