Let ABCD be a tangential quadrilateral and P be the center of the
inscribed circle (see the figure below). if S_{1} = area APB, S_{2}
= area BPC, S_{3} = area PCD and S_{4} = area APDH,
prove that S_{1} + S_{3}
= S_{2} + S_{4}.

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Geometry Problems

Open Problems

Visual Index

Ten problems: 1411-1420

All Problems

Quadrilateral

Tangential or Circumscribed Quadrilateral

Incenter, Inscribed circle

Circle

Circle Tangent Line

Triangle

Area

Triangle Area

Dynamic Geometry

GeoGebra

HTML5 and Dynamic Geometry

iPad Apps

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