MathDB
Turkish MO 1994 P2

Source: Turkish Mathematical Olympiad 2nd Round 1994

September 27, 2006
geometrycyclic quadrilateralgeometry unsolved

Problem Statement

Let ABCDABCD be a cyclic quadrilateral BAD<90\angle{BAD}< 90^\circ and BCA=DCA\angle BCA = \angle DCA. Point EE is taken on segment DADA such that BD=2DEBD=2DE. The line through EE parallel to CDCD intersects the diagonal ACAC at FF. Prove that ACBDABFC=2. \frac{AC\cdot BD}{AB\cdot FC}=2.