1. Question about homework? Any questions on the homework? (choose random problems)

2. 7.3 Proving Triangles Similar

3. Related Topic Remember we had to prove triangles congruent? Proving triangles similar is similar to proving triangles congruent but different The theorems to prove triangles similar are different

4. Postulate 7.1 Angle-Angle similarity (AA~) Postulate If two angles of one triangle are congruent to two angles of another triangle, then the triangles are similar R T S L P M

5. Theorem 7.1 Side-Angle-Side Similarity (SAS~) Theorem If an angle of one triangle is congruent to an angle of a second triangle, and the sides including the two angles are proportional, then the triangles are similar Examples: Notice the difference

6. Theorem 7.2 Side-Side-Side (SSS~) Theorem If the corresponding sides of two triangles are proportional, then the triangles are similar Examples:

7. Are the triangles similar? Why? Write the similar statement W R S V B 45

8. Are the triangles similar? Why? Write the similar statement P QR Z X Y 3 8 4 6

9. If the triangles are similar, find DE A C B D E 10 12 16 24 18

10. Vocabulary Indirect measurement – You use similar triangles and measurements to find distances that are difficult to measure directly

11. Example of indirect measurement

12. Homework/Classwork Pgs 385-387 #1,2, 4-20, 24-27, 32