# Synagoge 3.79

Pappus Alexandrinus, Synagoge, Book 3. Ancient Greek.

Canonical: https://interlinea.aeterna-institute.org/library/greek/pappus-alexandrinus/synagoge/3.79

79 νγ΄. Ἔστω θέσει καὶ μεγέθει δοθεῖσα ἡ ΑΒ, καὶ πρὸς ὀρθὰς ἡ ∠Γ, ἔστω δὲ τὸ ὑπὸ τῶν ΑΓΒ ἴσον τῷ ὑπὸ δοθείσης καὶ τῆς Γ∠· ὅτι τὸ ∠ σημεῖον ἅπτεται θέσει παραβολῆς. Τετμήσθω γὰρ ἡ ΑΒ δίχα τῷ Ε, καὶ πρὸς ὀρθὰς ἡ ΕΖ, καὶ τῷ ἀπὸ τῆς ΕΒ ἴσον ἔστω τὸ ὑπὸ τῆς δοθείσης καὶ τῆς ΕΖ· δοθὲν ἄρα τὸ Ζ. καὶ τῇ ΑΒ παράλληλος ἡ ∠Η· λοιπὸν ἄρα τὸ ἀπὸ τῆς ΕΓ, τουτέστιν τὸ ἀπὸ τῆς ∠Η, ἴσον ἐστὶ τῷ ὑπὸ τῆς δοθείσης καὶ τῆς ΖΗ. καὶ ἔστι δοθὲν τὸ Ζ· τὸ ἄρα ∠ σημεῖον ἅπτεται παραβολῆς κατερχομένης διὰ τῶν Α Ζ Β, ἧς ἄξων ἐστὶν ὁ ΕΖ.

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Pappus Alexandrinus, Synagoge, ed. Friedrich Hultsch. Text: The Greek Library, from the Perseus Digital Library and other open sources, CC BY-SA 4.0. Changes: apostrophes normalised and the text divided into reading sections by Interlinea.
License: CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0/). Source: https://thegreeklibrary.pages.lisn.upsaclay.fr/works/tlg2032.tlg001.local001/.