“P. Sherman, 42 Wallaby Way, Sydney!”

7.2 Similar

Polygons

SimilaritySimilar Polygons: Polygons having corresponding angles congruent and corresponding sides proportional (denoted “~”).

Similarity Ratio: The ratio of the lengths of corresponding sides in similar polygons.

1) Find mE

2) Find EHA

B C

D E

F G

H

ABCD ~ EFGH

72°

3in

6in

5in

SimilarityGiven LONM ~ QTSR below, find the value of x.

SimilarityDetermine whether the triangles are similar. If they are, write a similarity statement and give the similarity ratio.

15

18

1278°

67°A

B

C

16

24

2078°

35°D

E

F

Golden Ratio

Golden Rectangle: A rectangle that can be divided into a square and a rectangle that is similar to the original rectangle. The Golden Ratio is ≈ 1.618

An artist plans to paint a picture. He wants the canvas to be a golden rectangle with its longer horizontal sides 30cm wide. How high should the canvas be?

“Onions have layers.”

7.2 Similar Polygons

HW (7.2) Pg. 375, #2-12 even, 14-16 e,

22-28 e, 32-34 e