Dynamic Geometry Problem 1465: Tangential Quadrilateral, Incenter, Inscribed Circle, Equal Sum of Areas.

Let ABCD be a tangential quadrilateral and P be the center of the inscribed circle (see the figure below). if S1 = area APB, S2 = area BPC, S3  = area PCD and S4 = area APDH, prove that S1 + S3  = S2 + S4.


Static Diagram of Geometry Problem 1465

Poster of Problem 1465, Tangential Quadrilateral, Incenter, Inscribed Circle, Step-by-step Illustration, GeoGebra, iPad


Poster of Geometry Problem 1465 using iPad Apps

Poster of Problem 1465, Tangential Quadrilateral, Incenter, Inscribed Circle, Equal Sum of Areas, Chan Chan, Trujillo, Peru, Step-by-step Illustration, GeoGebra, iPad

Classroom Resource:
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Ten problems: 1411-1420
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Tangential or Circumscribed Quadrilateral
Incenter, Inscribed circle
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Circle Tangent Line
Triangle
Area
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