 | Science - 1844 - 434 pages
...proposition, too, would follow the converse of the first one, if ever the sum differed from 180". PROP. III. The three angles of every triangle are equal to' two right angles. B ' Let ABC be any equilateral trlanglfe ; ./\ / \ bisect its angles, which obviously will {[ •£... | |
 | Euclides - 1845 - 544 pages
...XXII. THEOREM. The opposite angles of any quadrilateral figure inscribed in a circle, are together equal to two right angles. Let ABCD be a quadrilateral figure in the circle ABCD. Then any two of its opposite angles shall together be equal to two right angles. Join AC, BD. And because... | |
 | Euclid, James Thomson - Geometry - 1845 - 380 pages
...XXII. THKOR. — The opposite angles of any quadrilateral figure described in a circle, J are together equal to two right angles. Let ABCD be a quadrilateral figure in the circle ABCD; If in the first diagram, CE were produced to meet AB, the first case might be proved in a similar manner.... | |
 | Plato - Atheism - 1845 - 460 pages
...say it is compelled to affirm, and does affirm this, with the same confidence as the proposition that the three angles of every triangle are equal to two right angles, or that two bodies cannot occupy the same space. Even this, notwithstanding it lies at the foundation... | |
 | Euclid, John Playfair - Euclid's Elements - 1846 - 332 pages
...PROP. XXII. THEOR. The opposite angles of any quadrilateral figure described in a circle, are together equal to two right angles. Let ABCD be a quadrilateral figure in the circle ABCD ; any its opposite angles are together equal to two right angles. Join AC, BD. The angle CAB is equal (21.... | |
 | Euclides - 1846 - 292 pages
...semicircle, is less than a right angle. Lastly, because ABCD is a quadrilateral figure in a circle, any two of its opposite angles are together equal to two right angles (3. 22) ; therefore the angles ABC, ADC are together equal to two right angles : But ABC is less than... | |
 | Edward Shaw - Masonry - 1846 - 342 pages
...straight lines AF and BD, and consequently making the angle at G equal to the angle F А С ; and since the three angles of every triangle are equal to two right angles, and since the angles FA С, С AB, BAE, are also equal to two right angles, and since F А С is equal... | |
 | David Benedict - Baptists - 1848 - 1026 pages
...not a head for the philosophy of language; and 1 say this with as liltle bad leeling as I say that the three angles of every triangle are equal to two right angles. " That Mr. President Beecher will be immersed in. one of the great American rivers, is now very improbable... | |
 | Euclid, Thomas Tate - 1849 - 120 pages
...of any quadrilateral figure inscribed in a circle, are together equal to two right angles. LetABCobe a quadrilateral figure in the circle ABCD; any two...because the three angles of every triangle are equal (i. 32.) to two right angles, the three angles of the triangle CAB, viz. the angles CAB, ABC, BCA,... | |
 | Elias Loomis - Conic sections - 1849 - 252 pages
...the sixth part of four right angles (Prop. II., Sch. 1), or the third part of two right angles. Also, because the three angles of every triangle are equal to two right angles, the two angles OAB, OBA are together equal to two thirds of two jj^—^C right angles; and since AO is... | |
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The opposite angles of any quadrilateral figure described in a circle, are toe/ether equal to two right angles. Let ABCD be a quadrilateral figure in the circle ABCD : any two of its opposite angles are together equal to two right angles. 
