Why We Use “X” as the Unknown in Math

The variable “x” is used widely in the mathematics of all cultures, American or not. But why?

Some explain it as a mistranslation from Arabic to Spanish, substituting Greek Chi (X) for Arabic “al-shalan.”

It could be Rene Descartes’ La Geometrie, one of the seminal works in math, that decided “x” should be used as a variable. But why? No one really knows.

Either way, math, along with science, is filled with English. Learn English to better understand these subjects!


Source: Why We Use "X" as the Unknown in Math.

Image: Mariusz Kucharczyk.