Lucio buys a table shaped like a regular hexagon and a rectangular tablecloth of area 1024cm2 whose shorter side equals the side of the hexagon and which covers exactly the portion of the table between two opposite sides. What is the area of the table, expressed in cm2?
Solution
Solution:
The answer is 1536.
Let ABCDEF be a regular hexagon representing the table; the tablecloth of area 1024cm2 covers exactly the rectangle ABDE. Letting O be the center of the hexagon and H,K be the points of intersection between the segments BD and OC, AE and OF, respectively, the triangles OAK, OEK, OBH and ODH are all congruent and have an area equal to half the area of the equilateral triangles ABO and DEO. It follows that the area of the rectangle ABDE equals four times the area of ABO, while the area of the table equals six times the area of ABO. We conclude that the area of the table is 46⋅1024cm2=1536cm2.
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Source: MathNet,
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