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Geometry NOTES Date: ________ Lesson 7-2: Similar Polygons Similar Polygons: ~ - same shape, different size - Corresponding angles are ≅. - Corresponding sides are in proportion Compare angles: A X, Compare ratios of sides: AB 6 2 XY 3 B Y CD 9 2 ZW 4.5 C Z BC 8 2 YZ 4 D W DA 4 2 WX 2 Because corresponding sides are proportional AND corresponding angles are congruent, ABCD ~ XYZW. Try These! Determine if the figures are similar or not. Support your reasoning. 1. Rectangles: 2. Pentagons: 3. Triangles: Similarity Ratio / Scale factor : the ratio of the lengths of corresponding sides in similar figures. 1. What is the scale factor of the triangles? Write the similarity statement. 2. ΔRST ~ ΔUVW. What is the scale factor? What is the value of x? . 3. ∆ABC ~ ∆EFG; Find EF. 4. Quad PQRS ~ Quad LMNO ; Find NO 5. ∆ XYZ ~ ∆EFD. Find the value of x. 6. LMNO ~ RQTS. Find the value of x. 7. a. Find the value of x. b. Find the value of y. 8. You make a scale drawing of a tree using 5 inches = 27 feet. If the tree is 67.5 feet tall, how tall is the scale drawing of the tree? Write and solve a proportion. HOMEWORK: pgs. 468 – 470 # 1-4, 10-16, 19-26