Properties of Similar Polygons

Lesson #4Pg. 131

Vocabulary

• Similar Polygons– Polygons that have the same shape

• Scale Factor– The ratio of the lengths of two corresponding sides

of two similar polygons

• Math Symbols– Congruent

• – Similar

• ~

What you will learn…

– Similar Polygons

– Finding missing measures

– http://www.youtube.com/watch?v=9IUI3jtSEWU

Real World Link

– Are the prints in proportion?

– Are the side lengths in proportion?

– What do you notice about the angles?

Figure Side Length (cm) Angle Measure (cm)

DE EF FD

LJ JK KL

D E F

L J K

Similar Polygons

• If two polygons are similar, then…– There corresponding angles are congruent– The measures of their corresponding sides are in

proportion

– SymbolsA

B

C

X

Y

Z

ABC XYZ :

Examples

• Determine whether rectangle HJKL is similar to rectangle MNPQ. Explain.

7 7

3

3

10 10

6

6

H

J K

L

N P

M Q

Examples

• Quadrilateral WXYZ is similar to quadrilateral ABCD

• Describe the transformations.

• Find the missing measure.

X

1312

10

24

m

15

A

D

W

B

YC Z

HC: PG. 135-136 (1-11)

CC: PG. 135-136 (1-5, 7, 9-11) 

WWW.IXL.COM H8

Homework