τῷ Ε κοινὴ καὶ ἀμφοτέροις. τῶν δὲ ἰσογωνίων τριγώνων αἱ περὶ τὰς ἴσας γωνίας πλευραὶ ἀνάλογον διὰ τὸ δ΄ τοῦ Ϛ΄ τῶν Στοιχείων. ὡς ἡ ΑΒ οὖν πρὸς τὴν ΒΕ, ἡ Ζ∠ πρὸς τὴν ∠Ε· καὶ ἐναλλάξ, ὡς ἡ ΑΒ πρὸς τὴν Ζ∠, ἡ ΒΕ πρὸς τὴν ∠Ε ὅπερ ἔδει δεῖξαι.
Scholia in Euclidis optica (scholia vetera). Scholia in Euclidem. ed. Johan Ludvig Heiberg, ed. H. Menge. United States. 2018.
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