A square and an equilateral triangle. The square is folded as shown. What is the angle α?
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Folding to pyramid
Tag: folding
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Folding a pentagon
One side of a regular pentagon is folded back and forth as shown. Are the six red line segments congruent?
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Folding magic
One corner of a rectangular piece of paper is folded as shown. Prove that the red line segments are concurrent.
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Folded napkin II
A unit square paper is folded as shown. What is the red area?
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The secret document
One corner of a rectangular piece of paper is folded back and forth to the opposite side. What is the proportion red : blue?
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The sneak peek
A rectangle with given side lengths is folded back and forth such that the corner touches the opposite side as shown. What is the minimal shaded fraction?
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Take five origami
Divide a rectangular piece of paper in five pieces of equal area. You only have a pair of scissors at your disposal, but you are allowed to make straight folds to guide you.
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The kingsize bed
A rectangle with an inscribed right triangle. What is ac/bd?
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The folded napkin
A square sheet of paper is folded symmetrically from a corner. If the fold length is 4, what is the area of the triangle formed by the other three corners?
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The bobline
A regular hexagon is folded back and forth along the dotted line. What fraction of the area is yellow?