β΄.
τὸ Β τῷ μεγέθει.
πεπορίσθω καὶ ἔστω ὁ τοῦ Γ πρὸς τὸ Δ λόγος. καὶ ἐπεί ἐστιν ὡς τὸ Α πρὸς τὸ Β, οὕτως τὸ Γ πρὸς τὸ Δ, ἐναλλὰξ ἄρᾳ ἐστὶν ὡς τὸ Α πρὸς τὸ Γ, οὕτως τὸ Β πρὸς τὸ Δ. ἴσον δὲ τὸ Α τῷ Γ· ἴσον ἄρα καὶ τὸ Β τῷ Δ· δέδοται ἄρα τὸ Β μέγεθος· ἴσον γὰρ αὐτῷ
πεπόρισται τὸ Δ.
Data. Euclid. ed. Johan Ludvig Heiberg, ed. Heinrich Menge. United States. 2016.
Sponsored by Harvard College Library.