Algebras (jabbre and maqabeleh) are geometric facts which are proved by propositions five and six of Book two of Elements.
As quoted in "A Paper of Omar Khayyam" by A.R. Amir-Moez in "Scripta Mathematica", 26, 1963.
Algebras (jabbre and maqabeleh) are geometric facts which are proved by propositions five and six of Book two of Elements.