Sum of any 3 sides of a quad div by 4th=>some 2 are equal
Source: RMO (Mumbai Region) 2015 P8
December 6, 2015
inequalitiesnumber theorygeometrygeometry proposed
Problem Statement
The length of each side of a convex quadrilateral is a positive integer. If the sum of the lengths of any three sides is divisible by the length of the remaining side then prove that some two sides of the quadrilateral have the same length.