Characterizations of Bicentric Quadrilaterals

نویسندگان

  • Martin Josefsson
  • M. Josefsson
چکیده

We will prove two conditions for a tangential quadrilateral to be cyclic. According to one of these, a tangential quadrilateral is cyclic if and only if its Newton line is perpendicular to the Newton line of its contact quadrilateral.

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تاریخ انتشار 2010