| John Reynell Morell - Geometry - 1871 - 156 pages
...quadrilateral is divided into two triangles, whose angles form those of the quadrilateral ; and as **the three angles of every triangle are equal to two right angles** or 180°, the angles of the quadrilateral must be equal to four right angles or 300°. From this it... | |
| Arthur Young - Meditation - 1873 - 222 pages
...it is compelled to affirm, and does affirm this, with the same confidence as the propositition 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... | |
| Euclides - 1874 - 342 pages
...22. — 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. Construction. Join... | |
| Euclid, James Bryce, David Munn (F.R.S.E.) - Geometry - 1874 - 234 pages
...angles are together equal to two right angles. Let ABCD be a quadrilateral figure inscribed in a circle, **any two of its opposite angles are together equal to two right angles. Join** the centre 0 to B and D. Then in both cases, the two angles at 0 are together double of the angle A... | |
| Edward Atkins - 1874 - 428 pages
...a semicircle, is less than a right angle. And, because ABCD is a quadrilateral figure in a circle, **any two of its opposite angles are together equal to two right angles** (III. 22); Therefore the angles ABC, ADC are together equal to two right angles. But the angle ABC... | |
| Edward J. Cowling Welch - Steam-engines - 1875 - 244 pages
...than a semicircle, is less than a right angle. And because ABCD is a quadrilateral figure in a circle, **any two of its opposite angles are together equal to two right angles** (Euc. III. 22) ; therefore the angles ABC, ADC are together equal to two right angles. But the angle... | |
| Edward Atkins - 1876 - 130 pages
...a semicircle, is less than a right angle. And, because ABCD is a quadrilateral figure in a circle, **any two of its opposite angles are together equal to two right angles** (III. 22); Therefore the angles ABC, ADC are together equal to two right angles. But the angle ABC... | |
| Robert Potts - Geometry, Plane - 1876 - 446 pages
...THEOREM. The opposite angles of any quadrilateral figure inscribed in a circle, art together equal to twu **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 ^ C, BD. And... | |
| Elias Loomis - Conic sections - 1877 - 458 pages
...is the sixth part of four right angles (Pr. 2, 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 right angles ; and since AO is equal to... | |
| Āryabhaṭa - 1878 - 100 pages
...right angles, a circle can be described about it. First let ABCD be a quadrilateral figure inscribed iu **the circle ABCD. Any two of its opposite angles are together equal to two right angles.** Because the angle ADB is equal to the angle ACB (P. 36) and the angle DCA to the angle DBA (P. 30).... | |
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