MathDB
LA + MB = LM inside a cyclic ABCD, angle bisector and parallel related

Source: Singapore Senior 2006

July 10, 2019
geometryangle bisectorcyclic quadrilateral

Problem Statement

Let ABCDABCD be a cyclic quadrilateral, let the angle bisectors at AA and BB meet at EE, and let the line through EE parallel to side CDCD intersect ADAD at LL and BCBC at MM. Prove that LA+MB=LMLA + MB = LM.
Back to ProblemsView on AoPS