[ª] , [©] , [^] , [¨]Incenter / In the case of two lines (2)(GC World : Various Problems ,Five centroids of triangle etc.)
The bisectors of two corners of the triangle are drawn, and intersection is called point D.
Let's move point A.
What is the relationship between ÚBAC and ÚBDC?

GC/Win


Forum of Geometric Constructor by Y.Iijima