Simple equations of the first degree in one unknown, of the type *ax=b*, are found in the oldest mathematical text-book which we possess, the Ahmes papyrus of about 1700 B.C., which was published with a German translation by Eisenlohr [Leipzig, 1877, E.A. Wallis Budge, London 1898]. This Egyptian document presents not only first degree equations together with symbols for the unknown quantity and the operations of addition and subtraction, but also shows traces of a study of simultaneous linear equations some two thousand years before the Christian Era.
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Published before 1923