The Virtue Signaling Version of 'X' the Unknown

The letter “X” represents the mysterious, the unknown, the forbidden and foreboding, x- rated, x-rays. x-factor. In mathematics it represents an unknown quantity or a variable. Why is this? You may have heard of a current trendy theory with the proper air of “woke”. Apparently “al-shay-un” is an Arabic word meaning an unknown thing. And used as such to mean unknown quantity in Arabic writings on algebra. But when Spanish scholars sought to translate these writings, turns out Spanish did not have an SH sound. So Spanish scholars used the closest sound they knew of, the Greek letter Chi, which resembles the Latin letter X. Bingo, there we have it! Although it does not seem to be clear why in translation the sound of the original word is relevant.