1. Bellwork Solve the problem below and turn it in. Have your homework out to check. Solve for x. (Note: Your answer will NOT be an integer!)

2. STUDENTS WILL BE ABLE TO IDENTIFY PROPORTIONAL SIDES AND CONGRUENT ANGLES OF SIMILAR POLYGONS GIVEN A DIAGRAM OR SIMILARITY STATEMENT. 7.2 Similar Polygons

3. Ponder…  How are the two giraffes the same/different?

4. Similar Polygons (Defn) Polygons that are similar are the same ______ but not necessarily the same_____! Shape Size They look the same, but they do not have to be congruent

5. Similar Polygons (Defn) Two things must be true if two polygons are to be similar ( )…their 1. corresponding angles are congruent 2. corresponding sides are proportional

6. Example 1  Are the two figures similar? If so, write a similarity statement and justify.

7. Scale Factor (Defn)  The ratio that compares the lengths of the corresponding sides of similar figures is called the scale factor.

8. Example 2 The polygons below are similar. 1. Write a similarity statement. 2. Find DE and DF. 3. Find the scale factor from left to right.scale factor

9. Example  Billy is building a model of Chicago out of toothpicks. If his model made the Willis tower 60 toothpicks tall, what is the scale factor?  What do we need to know to solve The Willis tower is 1450 feet tall A toothpick is 2.5 inches long.

10. Example 3  The pair of polygons are similar. Write a similarity statement, find PS and TS.

11. Ticket to Leave  If  ABC ~  DEC, find DE.

12. Homework  Pg. 392 # 1, 2, 4, 10, 14, 15, 19, 64, 68, 70