Similarity and Congruence
Lesson 9
Topics
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x 7KH6$6DQG$$VLPLODULW\SULQFLSOHVIRUWULDQJOHV
x 3URSHUWLHVRISDUDOOHOOLQHV
x %DVHDQJOHVRILVRVFHOHVWULDQJOHV
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x congruent polygons: 7ZRSRO\JRQVWKDWDUHVLPLODUZLWKVFDOHIDFWRUk DUHFRQJUXHQW
x isosceles triangle: $WULDQJOHZLWKDWOHDVWWZRVLGHVFRQJUXHQWLVLVRVFHOHV
x similar polygons: 7ZRSRO\JRQVDUHVLPLODULILQPRYLQJRQHGLUHFWLRQDERXWRQHSRO\JRQLWLV
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ż DOOVLGHOHQJWKVHQFRXQWHUHGLQWXUQPDWFKLQWKHVDPHUDWLR k.
ż DOODQJOHVHQFRXQWHUHGLQWXUQPDWFKH[DFWO\
The common ratio kRIWKHVLGHOHQJWKVLVFDOOHGWKHVFDOHIDFWRU
Notation
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x 7KHV\PERO#LVXVHGWRGHQRWHWKDWWZRSRO\JRQVDUHFRQJUXHQW