Turn Zhao Shuang’s argument into a modern proof of the Pythagorean Theorem

The Suan shu shu presents basic mathematics problems and solutions. It was most likely a handbook for day-to-day business transactions or affairs of government administration. It contains problems and solutions for field measurements of area, proportional exchange rates for agricultural millet and rice, distribution by proportion, short width division, and excess and deficiency. Some of the problems found in the Suan shu shu appear in the later text Jiuzhang suanshu; in five cases, the titles are exact matches. However, unlike the Jiuzhang suanshu, the Suan shu shu does not deal with problems involving right-angle triangles, square roots, cube roots, and matrix methods, which demonstrates the significant advancements made in Chinese mathematics between the writings of these two texts.

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