'exactly' originates from Latin, specifically the word 'exactus,' where 'ex-' meant 'out' and 'agere' meant 'to drive.' 'Answer' originates from Old English, specifically the word 'andswaru,' where 'and-' meant 'against' and 'swaru' meant 'affirmation.'

'exactus' transformed into the French word 'exact,' and eventually became the modern English word 'exactly' through Middle English. 'Andswaru' transformed into the Middle English word 'answere,' and eventually became the modern English word 'answer.'

Initially, 'exactly' meant 'precisely' and 'answer' meant 'response,' and these meanings have largely remained the same in modern usage.