Although there is not a single known inventor of the quadratic formula, its use dates back to the Middle Kingdom in Egypt. Greek mathematicians, such as Euclid and Diophantus also used early versions of the quadratic formula.
The first quadratic equation was used in Egypt, and this equation was further expanded by the Greeks using geometric methods. Euclid's work, called "Data," solves equations with quadratic formulas, and "Arithmetica" by Diophantus also solves the quadratic formula. However, these early works did not utilize both a positive and negative root. Indian mathematicians may have used the quadratic formula to design altars dating back to 500 B.C. Other Hindu and Persian mathematicians invented rules for the quadratic formula.