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 Subject: "Circumscribed quadrilateral" Previous Topic | Next Topic
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bitrak
Member since Jul-14-05
Jul-18-05, 05:02 PM (EST)     A quadrilateral ABCD is circumscribed about a circle and P,Q,R,S are the points of tangency of sides AB,BC,CD,DA respectively.Let a=AB, b=BC, c=CD, d=AD and p=QS, q=PR. Show that ac/(p^2)=bd/(q^2)

Member since Aug-14-05
Aug-19-05, 00:14 AM (EST)    In response to message #0

 I do not understand where your problem is. >A quadrilateral ABCD is circumscribed about a circle and >P,Q,R,S are the points of tangency of sides AB,BC,CD,DA >respectively.Let a=AB, b=BC, c=CD, d=AD and p=QS, q=PR. Show >that ac/(p^2)=bd/(q^2) If you make a simple drawing, you can be sure that: { a=c=p } and that { b=d=q }.Therefore, it is true for any number a*a/a^2 = 1 . Using this, you can be sure that each side of the equasion is equal to 1. And, of course, we all know that 1=1.

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