Geometry Problem 1372: Equilateral Triangle, Exterior Cevian, Inradius, Exradius, Altitude, Sketch, iPad Apps.

Proposition

In the figure below, ABC is an equilateral triangle with altitude h. D is a point on CA extended, r1 is the inradius of the triangle DAB and r2 is the exradius of the triangle DBC corresponding to BC. Prove that r1 + r2 = h.

BD is called an exterior cevian of triangle ABC
 

Geometry Problem 1372: Equilateral Triangle, Exterior Cevian, Inradius, Exradius, Altitude, Sketch, iPad Apps
 


Sketch and Typography of problem 1372 using iPad Apps


Sketch and typography of Geometry Problem 1366 using iPad Apps, Tutor, Square, Angle Bisector, Perpendicular, Concyclic Points, Circle

 


 

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