CK-12 Geometry-Concepts

http://www.ck12.org Chapter 7. Similarity

Example B

Determine if the following two triangles are similar. If so, write the similarity statement.

m^6 C= 39 ◦andm^6 F= 59 ◦. The angles are not equal, 4 ABCand 4 DEFare not similar.

Example C

Are the following triangles similar? If so, write the similarity statement.

BecauseAE||CD,^6 A∼=^6 Dand^6 C∼=^6 Eby the Alternate Interior Angles Theorem. Therefore, by the AA Similarity
Postulate, 4 ABE∼4DBC.

Watch this video for help with the Examples above.

MEDIA

Click image to the left for use the URL below.

URL: http://www.ck12.org/flx/render/embeddedobject/52547

CK-12 Foundation: Chapter7AASimilarityB

Vocabulary

Two triangles aresimilarif all their corresponding angles arecongruent(exactly the same) and their corresponding
sides areproportional(in the same ratio).