Geometry: An Interactive Journey to Mastery



Lesson 9: Similarity and Congruence

Solution

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ͼ௘6HHFigure 9.6௘ͽ

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and transversal AF௘ͽDQGYHUWLFDODQJOHV

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 7KXV'ABD and 'DEFVKDUHWZRDQJOHVVR'ABDa'DEFE\$$

E௘ͽ 1RWLFH

Side xLQWKHOHIWWULDQJOHPDWFKHVaLQWKHULJKWWULDQJOH

Side bLQWKHOHIWWULDQJOHPDWFKHVyLQWKHULJKWWULDQJOH

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 &URVVPXOWLSO\LQJ\LHOGVxy = ab.

Study Tip

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PDWFKLQJDQJOHVEHWZHHQWKHWZRWULDQJOHV

Pitfall

x 'RQ¶WIRUJHWWKDWLWLVSHUPLVVLEOHIRUWZRVLPLODU¿JXUHVWRKDYHRSSRVLWHRULHQWDWLRQV²WKDWLVWKDWWKH

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A

x

B

C

E

y

D F

b a

Figure 9.6