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GeometryHardOlympiad Geometry

Olympiad Geometry · Hard problem

△ABC≅△DEF\triangle ABC \cong \triangle DEF. The sides are AB=2x+yAB = 2x + y, BC=3x−yBC = 3x - y, AC=x+2yAC = x + 2y, DE=13DE = 13, and EF=12EF = 12. Find the perimeter of △DEF\triangle DEF.