A pictorial proof of the theorem,  is presented for a, b, c, and d > 0 and arbitrary real numbers s and t; it is an extended version of the following theorem:   The diagrams used in this proof can also help college students understand the concept of linearity.

fractions, ratio, mediant property, linearity.

Received: June 26, 2024; Accepted: July 12, 2024; Published: August 7, 2024

How to cite this article: Yukio Kobayashi, Proof without words: ,  Far East Journal of Mathematical Education 26(2) (2024), 71-77. http://dx.doi.org/10.17654/0973563124008

This Open Access Article is Licensed under Creative Commons Attribution 4.0 International License

References:
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