A square with two line segments. What’s the angle α?
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Remote corner II
Category: Beginner
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The cheese flag
Two squares, one of which has an extended side. What is orange : purple?
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Ticker tape
Three overlapping congruent rectangles of area X. What is purple-yellow+2*green?
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The pyramid chambres
Two rectangles inside an equilateral triangle. What fraction is red?
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Ice cube III
Two squares and an extended side. What’s the angle α?
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Fair and square II
Three squares and two diagonals. What is orange : blue?
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Centre court
Two concentric squares. H is the circumcentre of triangle CDE. What is the angle α?
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The rightward lean
A triangle with a median tilting to the right and two incircles. Prove that the blue area is larger than the red one.
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Teleportation of squares
Two circles of the same radius, with tangents to one circle from the center of the other. Show that two of the squares’ vertices line up with points on the other circle.
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Harmonious symmetry
Tangents to a circle intersect, and another line is drawn through that intersection. Show that the products of opposite sides of the blue quadrilateral are equal.