¶ 2019 AMC 10B Problem 8
Problem:
The figure below shows a square and four equilateral triangles, with each triangle having a side lying on a side of the square, such that each triangle has side length and the third vertices of the triangles meet at the center of the square. The region inside the square but outside the triangles is shaded. What is the area of the shaded region?
Answer Choices:
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Solution:
The height of each equilateral triangle is , so the side length of the square is . The area of the square is then , and the area of the shaded region is
The problems on this page are the property of the MAA's American Mathematics Competitions