Abe no Monjuin #12

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A circle, a square, and an equilateral triangle are nestled inside a right triangle. What is the side length of the blue triangle?

Sangakus

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Sangakus, or “mathematical tablets” in Japanese, are colorful geometric questions or solutions carved on wood. They were created between the 17th and 19th century by Japanese mathematicians who used to hang them in temples or shrines. 

Sangaku of

Konnoh Hachimanguo Shrine

(1859)

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Source: en.wikipedia.org

Katayamahiko

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We have two congruent circles of radius r and a square of side 2. What is the value of r?

Katayamahiko

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We have two congruent circles of radius r and a square of side 2.

 

 

 

 

 

 

 

What is the value of r?

Katayamahiko

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We have two congruent circles of radius r and a square of side 2. What is the value of r?