Geometry: An Interactive Journey to Mastery

Glossary

PHGLDQRIDWUDSH]RLGͼ௘௘ͽ: If a trapezoid has just one pair of parallel sides, then the line segment connecting

the midpoints of the two remaining sides is the median of the trapezoid. 6HHDOVR trapezoid.

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VLGHͼ௘(DFKWULDQJOHSRVVHVVHVWKUHHPHGLDQVDQGWKH\DOOSDVVWKURXJKDFRPPRQSRLQWFDOOHGWKHFHQWURLGRI

WKHWULDQJOH௘ͽ

PLGSRLQWͼ௘௘ͽ: $SRLQWM is a midpoint of line segment AB if M lies on the segment and AM = MB.

NJRQͼ௘௘ͽ: $SRO\JRQZLWKN sides. 6HHDOVR polygon.

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REWXVHWULDQJOHͼ௘௘ͽ: $WULDQJOHZLWKRQHLQWHULRUDQJOHWKDWLVDQREWXVHDQJOH6HHDOVRobtuse angle.

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SDUDERODͼ௘௘ͽ: Given a line m and a point F not on that line, the set of all points P equidistant from m and P

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SDUDOOHOͼ௘௘ͽ: 7ZROLQHVHDFKLQ¿QLWHLQH[WHQWDUHSDUDOOHOLIWKH\QHYHUPHHW

SDUDOOHORJUDPͼ௘௘ͽ: $TXDGULODWHUDOZLWKWZRSDLUVRISDUDOOHOVLGHV

SHUSHQGLFXODUͼ௘௘ͽ7ZROLQHVRUOLQHVHJPHQWVWKDWLQWHUVHFWDWDQDQJOHRIƒDUHSHUSHQGLFXODU

SHUSHQGLFXODUELVHFWRUͼ௘௘ͽ: 7KHSHUSHQGLFXODUELVHFWRURIDOLQHVHJPHQWLVDOLQHWKURXJKWKHPLGSRLQWRIWKH

segment and perpendicular to it. 6HHDOVRmidpoint.

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common value of this ratio is called pi and is denoted ʌ.

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SRO\JRQͼ௘௘ͽ: $SODQDU¿JXUHFRPSRVHGRIVWUDLJKWOLQHVHJPHQWVͼ௘FDOOHGVLGHVRUHGJHV௘ͽVRWKDW

x VLGHVLQWHUVHFWRQO\DWWKHLUHQGSRLQWVͼ௘WKHHQGSRLQWVDUHFDOOHGWKHYHUWLFHVRIWKHSRO\JRQ௘ͽ

x SUHFLVHO\WZRVLGHVPHHWDWHDFKHQGSRLQWDQG

x WZRVLGHVPHHWLQJDWDYHUWH[PDNHDQDQJOHGLIIHUHQWIURPƒ