1. Warm-Up: Review from 7.2 1.) Determine whether the two triangles are similar. If so, write the similarity statement and scale factor. If not, explain your reasoning. 2.) If △ ABC ∼ △ DEC, find x. Then, determine the lengths of the 2 missing sides.

2. 7.3: Similar Triangles Objectives: I will be able to… 1.Identify similar triangles 2.Recognize similar triangles in real life Vocabulary: AA ~

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

4. 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 Q P R

5. 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. Y X Z M P N

6. Are the triangles below similar? If yes, write the similarity statement and what similarity postulate/theorem you used. W X Y Z V

7. If AC = 6, AD = 10, BC = 9, CE = 6, is  ACB ~  DCE? D A B C E What is the scale factor? What theorem/postulate did you use?

8. Are the triangles similar? N L M Q P 106° 36° 30 20 33 Write the similarity statement. Find the scale factor. Find MN. 11:10 MN = 22

9. Homework: Pg. 484 # 16-18, 24, 29, 40

10. A 6.5 ft tall car standing next to an adult elephant casts a 33.2 ft shadow. If the adult elephant casts a shadow that is 51.5 ft long then how tall is the elephant?

11. Indirect Measurement: On a windy day, you notice another student outside in the front of the school whose jacket has been carried up to the top of the flagpole. As you watch this student attempt to climb the flagpole to retrieve their jacket you start to wonder exactly how tall the flagpole is. Since you have plenty of time to ponder as you are watching the student climb you begin to realize things… You notice that you are exactly 6 feet tall and you are currently casting (as your friend tells you by walking from heel to toe) a three foot shadow. You then figure out that the flagpole is casting an 18 foot shadow. Assuming that the sun’s rays are forming the same angle on you and the flagpole, what is the height of the flagpole?