Two squares and an equilateral triangle. The three red line segments meet in a point. What is the yellow fraction?
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The meeting point
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Alien mothership attacks dome city
Two semicircles with parallel bases. Show that HF and GE intersect on the perpendicular line to AC above A.
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The sunny side
An equilateral triangle inside a rectangle. What’s red : yellow : blue?
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Draw the line
A square and an equilateral triangle inside a right triangle. Prove that the three red vertices are collinear.
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Another angle
Three congruent squares share three vertices. What’s the angle α?
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The maternal bond
Three tangent semicircles and a circle. One tangency point is shown. Prove that red : green = yellow : blue.
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The cocktail
A triangle with two circles and two line segments. Prove that it is isosceles.
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Voting eccentric
A square with a circle and a tangent. The tangency point lies on the diagonal. What fraction is red?
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The bike chain
A square containing a semicircle, a circle and two tangents. What’s the angle α?
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The Czech flag
A square is divided in three parts. What fraction is red?