The words ex, x sound the same but have different meanings and spellings. Why do ex, x sound the same even though they are completely different words?
The answer is simple: ex, x are homophones of the English language.
Not including; without: a stock price ex dividend.
Business Free of any transport or handling charges incurred before removal from a given location: bought the goods ex warehouse.
From, but not having graduated with, the class of: a Columbia alumnus, ex '70.
The letter x.
The 24th letter of the modern English alphabet.
Any of the speech sounds represented by the letter x.
The 24th in a series.
Something shaped like the letter X.
Definitions from The American Heritage® Dictionary of the English Language, 4th Edition and Wordnik.
Homophones (literally "same sound") are usually defined as words that share the same pronunciation, regardless of how they are spelled.