A square containing an isosceles triangle. What’s the angle α?
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The camping
Tag: triangle
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Hidden perfection
Two squares and two equilateral triangles. Prove that the red vertices also form an equilateral triangle.
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The green diamond
Two equilateral triangles are placed side by side. The common (blue) side is extended. What is red : blue?
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The beehive
Three regular hexagons, one centre and a triangle. What fraction of the total area is orange?
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Launch the ball
Express the circle area in terms of the isosceles triangle area A and its side length a.
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It’s all right II
A regular pentagon and a right triangle. What’s the angle α?
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Bond of union
Two intersecting circles with two inscribed triangles and two line segments through an intersection point. Prove that the triangles are similar.
Co-author: Marshall W. Buck.
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Centre of attraction
An equilateral triangle with two perpendiculars to a point that is at the same height as the triangle centre. What is red : yellow?
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The chessboard hallucination
Behold a 13-14-15 triangle. The 15-long side is dissected into 5 equal parts and the 14-long side is dissected into 7 equal parts. What is the difference between the red and green areas?
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The personal letter
Two rectangles share two vertices. What’s the green fraction?