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UKMT Junior Mathematical Olympiad, 2021

Geometry Difficulty 3.0 AMC 10/12 Prove it United Kingdom

A unit square has an equilateral triangle drawn inside it, with a common edge. Four of these squares and triangles are placed together to make a larger square. Four vertices of the triangles are joined up to form a square, which is shaded and shown in the diagram. What is the area of the shaded square?

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