Objective: To use AA, SAS and SSS similarity statements. Chapter 8 Lesson 3 Objective: To use AA, SAS and SSS similarity statements.

Angle-Angle Similarity (AA ~) Postulate                                                                                    If two angles of one triangle are congruent to two angles of another triangle, then the triangles are similar. ∆TRS ~ ∆PLM

Example 1: Using the AA~ Postulate Explain why the triangles are similar. Write a similarity statement.                                                                                                  RSW        VSB because vertical angles are congruent.  R     V because their measures are equal. ∆RSW ~ ∆VSB by the Angle-Angle Similarity Postulate.

Example 2: Using the AA~ Postulate Explain why the triangles are similar. Write a similarity statement.                                                                                                  B X A K M 58° ∆AMX~∆BKX by AA~ Postulate

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. Theorem 8-2   Side-Side-Side Similarity (SSS ~) Theorem If the corresponding sides of two triangles are proportional, then the triangles are similar.

Example 3: Using Similarity Theorems                                                                                     Explain why the triangles must be similar. Write a similarity statement. QRP     XYZ because they are right angles. Therefore, ∆QRP ~ ∆XYZ by the SAS ~ Theorem

Example 4: Using Similarity Theorems Explain why the triangles must be similar. Write a similarity statement.                  ∆ABC ~ ∆EFG by SSS~ Theorem

Assignment Pg. 435 #1-9, 22, 24-27