7.3 Similar Triangles (~s) AA Similarity Corresponding angles must be  SSS Similarity Corresponding sides must be proportional SAS Similarity Two sides must be proportional with the included angles 

Given: BD || AE ACE ~ BCD AA~ C Corresponding Angles Reflexive Angle

Are these triangles similar? 75 36 45 12 15 25 All Reduce to 1/3. s are ~ because of SSS ~.

Are these triangles similar? 6 4 2 3 Sides are proportional. The right angles are . s are ~ because of SAS ~

Example #1 Yes, by AA~ G  M F  L H  K GFH ~ MLK 37 43 F H G M K L Yes, by AA~ G  M F  L H  K GFH ~ MLK Determine whether the triangles are similar. If so, tell which similarity test is used and write a similarity statement.

Example #2 Find the value of x. 18 12 x 8 14 So, the triangles are similar by SAS ~.

Example #3 2 meters x meters 0.4 meters 1.5 meters The shadow of a flagpole is 2 meters long at the same time that a person’s shadow is 0.4 meters long. If the person is 1.5 meters tall, how tall is the flagpole?

Theorem 7.3 Similarity of Triangles is reflexive, symmetric and transitive. Homework #47 p. 401 7-11, 14-21, 29, 31-32 Quiz Monday