Dynamic Geometry 1479: Triangle, Circumcircle, Angle Bisector, Perpendicular Bisector, Chord, Concyclic Points, Parallel Lines, Step-by-step Illustration

For a triangle ABC with circumcircle c1 and internal angle bisector BD (see diagram) let EF be perpendicular to BD, GH perpendicular bisector of AE, and JK perpendicular bisector of CF. Chord HL passes through E and chord KM passes through F, Prove that (1) Points M, E, F, and L are concyclic; (2) EF and HK are parallel.


Static Diagram of Problem 1479

Dynamic Problem 1479 Triangle, Circumcircle, Angle Bisector, Perpendicular Bisector, Chord, Concyclic Points, Parallel Lines, Step-by-step Illustration, iPad Apps


Poster of problem 1479 using iPad Apps

Dynamic Geometry 1479: Triangle, Circumcircle, Angle Bisector, Perpendicular Bisector, Chord, Concyclic Points, Parallel Lines Using GeoGebra, iPad Apps

Classroom Resource:
Interactive step-by-step animation using GeoGebra

This step-by-step interactive illustration was created with GeoGebra.

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