[nbabitskiy]

The proof is on the left, and doesn't require algebra. You can use another picture for the right part, like this https://microexcel.ru/wp-content/uploads/2020/05/kvadrat-sum...

(it also uses algebraic notation which can be ignored)

[IshKebab]

Pythagorus's theorem is literally written using algebra. You can't even write it down without algebra.

[pritambaral]

algebraic notation != algebra

It can totally be written without "algebra"; it's not the notation that contains the idea, it's only the idea that happens to be often expressed in this notation. I could use any other notation, or even plain English, to express the idea, if I didn't mind the extra verbosity.

For Example:

1. The Berlin Papyrus 6619 (from 2000-1786 BC Egypt) uses prose [1]

2. The Ancient Chinese mathematical text Zhuobi Suanjing uses both prose and a pictorial notation [2]

3. The Baudhāyana Shulbasūtra (from 800-500 BC), a set of mathematical instructions for use in the construction of Vedic fire-altars, uses Sanskrit prose describing geometric constructions using rope [3] [4].

[1] https://en.wikipedia.org/wiki/Berlin_Papyrus_6619#/Connectio...

[2] https://commons.wikimedia.org/wiki/File:Chinese_pythagoras.j...

[3] https://en.wikipedia.org/wiki/Baudhayana_sutras#Pythagorean_...

[4] https://en.wikipedia.org/wiki/Shulba_Sutras#Pythagorean_theo...