Math · 2
Who invented the equals sign (=) in 1557?
Answer
Robert Recorde
Welsh mathematician Robert Recorde introduced the equals sign in his 1557 work 'The Whetstone of Witte', choosing two parallel lines because 'no two things can be more equal.' Before this, mathematicians wrote out the phrase 'is equal to' in full.
💡 Did you know?
The equals sign (=) didn't exist until 1557 when Robert Recorde invented it—mathematicians literally wrote out 'is equal to' before then.
Other options people guess
- John Napier
- François Viète
- Simon Stevin
Topics
- history-of-mathematics
- notation
- 16th-century
- symbols
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