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Explain how the thirteen pieces making up the regular hexagon shown in the diagram can be re-assembled to form three smaller regular hexagons congruent to each other.
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If the sides of the triangle in the diagram are 3, 4 and 5, what is the area of the shaded square?
Draw all the possible distinct triangles on a 4 x 4 dotty grid. Convince me that you have all possible triangles.