MathDB

3.

Part of 2023 Polish Junior Math Olympiad First Round

Problems(1)

2023 Polish Junior Math Olympiad Round 1 P3

Source:

5/21/2023
Let ABCDABCD be a rectangle. Point EE lies on side ABAB, and point FF lies on segment CECE. Prove that if triangles ADEADE and CDFCDF have equal areas, then triangles BCEBCE and DEFDEF also have equal areas.
geometry