Two squares and three line segments. What’s the angle α?
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Meeting halfway
Month: February 2023
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Crossing mountains
A rectangle with four line segments. What’s brown : blue?
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On a tangent
Two tangent circles and their three common tangents. Two secants meet on the internal tangent. Prove that the three red points are collinear.
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A square deal
A regular hexagon and a square share a vertex. What’s the angle α?
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The balloon incident
A circle with a red and a green tangent. The two tangency points are shown. Prove that the blue and red line segments are parallel.
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The pink diamond
Two congruent rectangles inside a square. What fraction of the square is the rectangle overlap?
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Diamond life
Two equilateral triangles and one centre. What’s green : red?
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The new normal
Two equilateral triangles are placed as shown. Their centres are connected as well as their intersection points. What’s the angle α?
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The radical
Two intersecting circles and a common tangent. The two tangency points are shown in black. Prove that the three red points are collinear.
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Getting stuck
A regular pentagon and a circle through two of its vertices and its centre. What’s the angle α?