In todays modern notation of Roman numerals: VI-XI-MCMLXXXIX
Note that the ancient Romans would have wrote out the equivalent of 1989 differently as we now do today
To write 9 11 1989 in Roman numerals, you would represent each individual number as follows: 9 is represented as IX, 11 is represented as XI, and 1989 is represented as MCMLXXXIX. So, 9 11 1989 in Roman numerals would be IX XI MCMLXXXIX.
The number 11 can be represented by the Roman numeral XI
XX.XI.MCMLXXXIX
XI
10/11/89 in Roman numerals is X - xi - lxxxix
To write 19-11-1987 in Roman numerals, you would write it as XIX-XI-MCMLXXXVII.
In today's notation of Roman numerals: VII-XI-MCMLXXXIX
The date 14-11-2004 can be represented by the Roman numerals XIV.XI.MMIV
It is: VIII-XI-XI
15th November, 1999 is XV. XI. MCMXCIX in Roman numerals.
In today's terms: XI-I-MCMLXXXIX
XI - IV - MCMLXXXIX