The 14th century saw the development of new mathematical concepts to investigate a wide range of problems.Grant, Edward and John E. Murdoch (1987), eds., Mathematics and Its Applications to Science and Natural Philosophy in the Middle Ages, (Cambridge: Cambridge University Press) . The two widely used arithmetic symbols are addition and subtraction, + and −. The plus sign was used by 1360 by Nicole OresmeMathematical Magazine, Volume 1. Artemas Martin, 1887. Pg 124His own personal use started around 1351. in his work Algorismus proportionum.Der Algorismus proportionum des Nicolaus Oresme: Zum ersten Male nach der Lesart der Handschrift R.40.2. der Königlichen Gymnasial-bibliothek zu Thorn. Nicole Oresme. S. Calvary & Company, 1868. It is thought an abbreviation for "et", meaning "and" in Latin, in much the same way the ampersand sign also began as "et". Oresme at the University of Paris and the Italian Giovanni di Casali independently provided graphical demonstrations of the distance covered by a body undergoing uniformly accelerated motion, asserting that the area under the line depicting the constant acceleration and represented the total distance traveled.Clagett, Marshall (1961) The Science of Mechanics in the Middle Ages, (Madison: University of Wisconsin Press), pp. 332–45, 382–91. The minus sign was used in 1489 by Johannes Widmann in Mercantile Arithmetic or Behende und hüpsche Rechenung auff allen Kauffmanschafft,.Later early modern version: A New System of Mercantile Arithmetic: Adapted to the Commerce of the United States, in Its Domestic and Foreign Relations with Forms of Accounts and Other Writings Usually Occurring in Trade. By Michael Walsh. Edmund M. Blunt (proprietor.), 1801. Widmann used the minus symbol with the plus symbol, to indicate deficit and surplus, respectively. In Summa de arithmetica, geometria, proportioni e proportionalità,Summa de Arithmetica: Geometria Proportioni et Proportionalita. Tr. Sum of Arithmetic: Geometry in proportions and proportionality.Arithmetical Books from the Invention of Printing to the Present Time. By Augustus De Morgan. p 2. Luca Pacioli used symbols for plus and minus symbols and contained algebra.Much of the work originated from Piero della Francesca whom he appropriated and purloined.
