Cardano, Geronimo, Opvs novvm de proportionibvs nvmerorvm, motvvm, pondervm, sonorvm, aliarvmqv'e rervm mensurandarum, non solùm geometrico more stabilitum, sed etiam uarijs experimentis & observationibus rerum in natura, solerti demonstratione illustratum, ad multiplices usus accommodatum, & in V libros digestum. Praeterea Artis Magnae, sive de regvlis algebraicis, liber vnvs abstrvsissimvs & inexhaustus planetotius Ariothmeticae thesaurus ... Item De Aliza Regvla Liber, hoc est, algebraicae logisticae suae, numeros recondita numerandi subtilitate, secundum Geometricas quantitates inquirentis ...

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              quadrati pentagoni, & eptagoni æquilaterorum nota: & etiam
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              ſubtenſorum duobus ex his. </s>
              <s id="id001782">Sit, gratia exempli, a b 3 & b c <02> 11 1/4m:
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              1 1/2, ut prius, & ponatur b d diameter, erit ad <02> 27 & c d <02> v 22 1/2 m:
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              <02> 101 1/4, quam ducemus in a b, & fiet <02> v 202 1/2 m: <02> 8201 1/4. Duce­
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              mus itidem <02> 27 a d in b c <02> 11 1/4 m: 1 1/2 fiet <02> 303 3/4m: <02> 60 3/4, hoc to­
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              tum diuide per 66, quæ eſt b: fiet a c <02> 8 7/16 m: <02> 1 11/16 p: <02> v: 5 45/72 m: <02>
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              6 1701/5184. Nec credas te errare, quoniam latus pentagoni eſſet, ac ſi an­
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              gulus b rectus eſſet: ſed quia eſt obtuſus, ideo a c eſt alia linea, &
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              maior latere pentagoni. </s>
              <s id="id001783">Et ſimiliter ſi a b, & a c notæ eſſent, utpo­
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              te a b 3, ut prius a c 5 dico, quòd b c nota eſt: nam a d erit <02> 27, &
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              quia ex b d in a c fit 30, fiet ex b c in a d pos <02> 27, et ex a b in c d <02> 324
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              m: 9 quad. </s>
              <s id="id001784">igitur 30 m: pos <02> 27 æquantur <02> 324 m: 9 quad. </s>
              <s id="id001785">quare
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              900 p: 27 quad. </s>
              <s id="id001786">m: pos <02> 97200
                <expan abbr="æquãtur">æquantur</expan>
              324 m: 9 quad. </s>
              <s id="id001787">igitur 576
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              p: 16 quad. </s>
              <s id="id001788">ęquantur pos <02> 97200. Quadratum igitur p: 36 ęquan­
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              tur pos <02> 379 11/16, erit ergo b c <02> v: <02> 94 59/64 p: <02> 58 59/64 & ſimiliter ſi a c
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              ſit nota, puta 4 erit a b ſubtenſa dimidio arcus a c nota. </s>
              <s id="id001789">Erit enim a e
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              2 ergo d e 3 p: <02> 5 et b e 3 m: <02> 5,
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              a b <02> v: 18 m, <02> 180. Igitur hoc
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              modo diuidendo, iungendo, & detrahendo habebimus ex quatu­
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              or illis ſimplicibus trianguli quadrati. </s>
              <s id="id001790">Pentagoni, & eptagoni in
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              numeras linearum magnitudines in circulo. </s>
              <s id="id001791">Et ſimiliter quouis mo
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              do, ut dictum eſt, in quauis figura æquilatera, utpote ſuppoſito
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                <figure id="id.015.01.117.1.jpg" xlink:href="015/01/117/1.jpg" number="111"/>
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              quod deſcriptum ſit non angulum in
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              circulo æquilaterum, quod etiam erit
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              æquiangulum, & ſit arcus a b duplus
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              arcui a c, erit angulus a c b duplus an­
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              gulo a b c, & angulus b a c in portione
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              b d e c ſexcuplus a b c, & triplus a c b.
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              </s>
              <s id="id001792">Erit ergo per demonſtrata proportio
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              b a ad a c, uelut a c, & c b, ad a b: pro­
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              portio autem a b arcus ad a c, ex ſup­
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              poſito maior eſt proportione rectæ a b ad a c, igitur etiam propor­
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              tione a c & c b ad a b, ergo duo latera trianguli ad tertium minorem
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              habent proportionem, quam arcus ad arcum, quanto rectæ ad re­
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              ctam minor eſt. </s>
              <s id="id001793">Sit rurſus in triangulo b e d quomodolibet modo
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              ſit angulus b d e quadruplus angulo b e d, & diuidatur d per ęqua­
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              lia ducta d f, erit igitur proportio f d, d e ad f e, ut e f ad f d, ſed e f ad
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              f b ut d e ad d b. </s>
              <s id="id001794">igitur proportio b d, d e ad f b
                <expan abbr="cõpoſita">compoſita</expan>
              ex propor­
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              tionibus e f ad f d, & e d ad d b. </s>
              <s id="id001795">Proportio igitur b d, d e ad f b, ut
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              producti ex e f in e d ad productum ex d fin d b. </s>
              <s id="id001796">Rurſus ponamus,
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                <arrow.to.target n="marg368"/>
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              quod in quadrangulo a b c d primæ figuræ ſit a b 4 b c 3 c d 5 ad 6
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              dico, quòd ſpatium contentum erit notum. </s>
              <s id="id001797">Ductis rectis a c & b d </s>
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