MathDB

2

Part of 2008 South africa National Olympiad

Problems(1)

Products of sides and diagonals in a quadrilateral

Source: South African MO 2008 Q2

5/27/2012
Let ABCDABCD be a convex quadrilateral with the property that ABAB extended and CDCD extended intersect at a right angle. Prove that AC⋅BD>AD⋅BCAC\cdot BD>AD\cdot BC.
geometry unsolvedgeometry