MathDB
integer ABCD, AB=AD, BC=CD, <ABC=<BCD=<CDA 2020 BMT Team 20

Source:

January 7, 2022
geometryequal segmentsequal angles

Problem Statement

Non-degenerate quadrilateral ABCDABCD with AB=ADAB = AD and BC=CDBC = CD has integer side lengths, and ABC=BCD=CDA\angle ABC = \angle BCD = \angle CDA. If AB=3AB = 3 and BDB \ne D, how many possible lengths are there for BCBC?