MathDB

Determine tangency points

Source: APMO 1995

March 11, 2006

geometrycircumcirclecyclic quadrilateralpower of a pointradical axisgeometry unsolved

Problem Statement

Let

PQRS

be a cyclic quadrilateral such that the segments

PQ

and

RS

are not parallel. Consider the set of circles through

P

and

Q

, and the set of circles through

R

and

S

. Determine the set

A

of points of tangency of circles in these two sets.