Why are letters used in algebra?

Algebra has made its way into many jokes, becoming a pet hate for many school kids. Peppered with letters and confusing mathematical signs, it may be a fun hobby for those who like to solve a mystery, but hardly the way most kids seeing themselves preparing for their future.

The word "algebra" itself is a Latin form of the Arabic word Al-Jabr ("casting") and comes from a mathematics book written by a famous Persian mathematician n the 9th century.

Both letters and numbers are easily distinguishable to everyone as a form of communication. Drawing on the alphabet for symbols means that missing numbers are easily identified in an equation.

Letters are also found easily on most keyboards, and are written the same (unlike other markers such as shapes and symbols).

The English (Or latin) version of the Greek letter χ (chi) was the first letter of the Arabic word for ‘something’. Quite literally – this letter is representing something, but we don’t know what.

In short it is the English (or Latin) version of the Greek letter χ (chi), which was the first letter of the transliteration of the Arabic word for 'something', which was used in the original algebra texts.

As a letter that is often associated with mystery or the uknown, it’s a good choice to replace a missing number with Z being an obvious third choice.

The second most common letters are a, b, c, most probably because they are at the start and end of the alphabet. Longer equations can easily use a lot more letters, depending on exactly how many variables are missing from an equation.