1. Similarity Exploration Use a protractor and a ruler to draw two noncongruent triangles so that each triangle has a 40 0 angle and a 60 0 angle. What can you determine about these figures? Why?

2. Proving Triangles Similar Students will be able to prove triangles similar using the AA, SSS, SAS similarity theorem.

3. Angle-Angle Similarity Postulate (AA~ Post.) If two angles of one triangle are congruent to two angles of another triangle, then the two triangles are similar. If  JKL   XYZ and  KJL   YXZ, then  JKL   XYZ. J K L X Y Z

4. Proportionality a. Write the similarity statement. b.Write the statement of proportionality. c.Find m  TEC. d.Find ET and BE. E T B C W 20 34 0 79 0 12 3

5. State if the triangles in each pair are similar. If so, state how you know they are similar and complete the similarity statement.

8. Not similar

9. Find the missing length. The triangles are similar. x = 9

10. Find the missing length. The triangles are similar. x = 9

11. Find JU. The triangles are similar. x = 24

12. Find PW. The triangles are similar. x = 11

13. Given: Prove:  WVX ~  ZYX W V X Z Y Statements Reasons

14. Given:  ABC is a right triangle, AD is an altitude Prove:  ABC   DAC A B C D StatementsReasons

15. Theorem 8.2 Side-Side-Side (SSS) Similarity Theorem If the corresponding sides of two triangles are proportional, then the triangles are similar. If, then  ABC   PQR. A B C P Q R

16. Theorem 8.3 Side-Angle-Side (SAS) Similarity Theorem If an angle of one triangle is congruent to an angle of a second triangle and the lengths of the sides including these angles are proportional, then the triangles are similar. If  X   M and, then  XYZ   MNP. X Y Z M N P