1. 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 

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

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

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

5. Example #1 Yes, by AA~ G  M F  L H  K GFH ~ MLK37 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.

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

7. 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?

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