MathDB
Bash Bash Bash

Source: Bulgaria National Olympiad 2023 Problem 4

April 9, 2023
geometryareaconvex quadrilateral

Problem Statement

Prove that there exists a unique point MM on the side ADAD of a convex quadrilateral ABCDABCD such that SABM+SCDM=SABCD\sqrt{S_{ABM}}+\sqrt{S_{CDM}} = \sqrt{S_{ABCD}} if and only if ABCDAB\parallel CD.