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Bellwork Solve the problem below and turn it in. Have your homework out to check. Solve for x. 2 x 3 4 x 1 5 (Note: Your answer will NOT be an integer!) STUDENTS WILL BE ABLE TO IDENTIFY PROPORTIONAL SIDES AND CONGRUENT ANGLES OF SIMILAR POLYGONS GIVEN A DIAGRAM OR SIMILARITY STATEMENT. 7.2 Similar Polygons Ponder… How are the two giraffes the same/different? Similar Polygons (Defn) Polygons that are similar are the same ______ Shape but not necessarily Size the same_____! 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 Example 1 Are the two figures similar? If so, write a similarity statement and justify. Scale Factor (Defn) The ratio that compares the lengths of the corresponding sides of similar figures is called the scale factor. 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. 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 The do we need to know to solve Willis tower is 1450 feet tall A toothpick is 2.5 inches long. Example 3 The pair of polygons are similar. Write a similarity statement, find PS and TS. Ticket to Leave If ABC~ DEC, find DE. Homework Pg. 392 # 1, 2, 4, 10, 14, 15, 19, 64, 68, 70