François Viète

François Viète (; 1540 – 23 February 1603), known in Latin as Franciscus Vieta, was a French mathematician whose work on new algebra was an important step towards modern algebra, due to his innovative use of letters as parameters in equations. Because of this, Viète is sometimes called "the father of modern algebraic notation". He was a lawyer by trade, and served as a privy councillor to both Henry III and Henry IV of France. Provided by Wikipedia