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    15-75-90 on the quarter circle

    Mar
    30
    less than 1 minute read

    On this page

    I just saw a nice visual proof of the ratios for the 15-75-90 on the internet via @ilarrosac.   This one works via symmetry and the Pythagorean theorem. 

    Tags: 15-75-90, geometry

    Updated: March 30, 2022

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