Geometry: An Interactive Journey to Mastery



Glossary

Glossary

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acute angle ͼ௘௘ͽ$QDQJOHZLWKPHDVXUHVWULFWO\EHWZHHQƒDQGƒLVDFXWH

DFXWHWULDQJOHͼ௘௘ͽ $WULDQJOHZLWKHDFKRILWVWKUHHLQWHULRUDQJOHVDFXWH6HHDOVRacute angle.

DOWHUQDWHLQWHULRUDQJOHVͼ௘௘ͽ: Given a pair of lines and a transversal, a pair of nonadjacent angles sitting

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that angle.

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DUFOHQJWKͼ௘௘ͽ: The length of an arc of a circle. 6HHDOVRarc.

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FLUFXPFHQWHURIDWULDQJOHͼ௘௘ͽ: The center of the circumcircle of a triangle is its circumcenter. It is the

ORFDWLRQZKHUHWKHWKUHHSHUSHQGLFXODUELVHFWRUVRIWKHWULDQJOHFRLQFLGH6HHDOVRcircumcircle of a triangle.

FLUFXPFLUFOHRIDWULDQJOHͼ௘௘ͽ: For each triangle, there is a unique circle that passes through the vertices of the

triangle. This circle is the circumcircle of the triangle.