area of polygon AQPBO does not change when points P,C move
Source: China Northern MO 2009 p6 CNMO
December 12, 2020
geometryfixedarea
Problem Statement
Given a minor sector (Here minor means that ). is the centre , chose a point on arc ,Let be a point on segment , join , , draw a line through parallel to , the line meet at point ,join . Prove that the area of polygon does not change when points move .
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