Books Books 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. Euclid in Paragraphs: The Elements of Euclid: Containing the First Six Books ... - Page 71
by Euclid - 1845 - 199 pages ## The Evidences of Christianity in Their External Or Historical Division ...

Charles Pettit McIlvaine - Apologetics - 1832 - 534 pages
...In mathematical reasoning, our knowledge is greater than our ignorance. 'When you have proved that the three angles of every triangle are equal to two right angles, there is an end of doubt, because there are no materials for ignorance to work up into phantasms; but... ## The Elements of Euclid; viz. the first six books, together with the eleventh ...

Euclides - 1834 - 518 pages
...ABCD be a quadraliteral figure in the circle ABCD : any two of its opposite angles shall together be equal to two right angles. Join AC, BD : and because the three angles of every tri• 32. 1. angle are equal * to two right angles, the three angles of the triangle CAB, viz. the... ## The Elements of Euclid: Viz. the First Six Books, Together with the Eleventh ...

Euclid - 1835 - 540 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...Join AC, BD; and because the three angles of every tria32. 1. angle are equal" to two right angles, the three angles of the triangle CAB, viz. the angle... ## Standard Works, Volumes 1-20

1835 - 582 pages
...certainty. In mathematical reasoning our knowledge is greater than our ignorance. When you have proved that the three angles of every triangle are equal to two right angles, there is an end of doubt ; because there are no materials for ignorance to work up into phantoms; but... ## The Element of Geometry

John Playfair - Geometry - 1836 - 114 pages
...PROP. XIV. THEOR. The opposite angles of any quadrilateral figure described in a circle, are together equal to two right angles. Let ABCD be a quadrilateral...because the three angles of every triangle are equal (5. 2.) to two right angles, the three angles of the triangle CAB, viz. the angles CAB, ABC, BCA are... ## Elements of Geometry: Containing the First Six Books of Euclid, with a ...

John Playfair - Euclid's Elements - 1836 - 488 pages
...angles of any quadrilateral figure described in a circle, are together equal to two right angles, t , Let ABCD be a quadrilateral figure in the circle ABCD...opposite angles are together equal to two right angles, a 21. 3. Join AC, BD. The angle CAB is equal a to the angle CDB, because they are in the same segment... ## Elements of Plane Geometry According to Euclid

Andrew Bell - Euclid's Elements - 1837 - 240 pages
...XXII. THEOREM. The opposite angles of any quadrilateral figure described in a circle, are together equal to two right angles. Let ABCD be a quadrilateral...angles of every triangle are equal to two right angles (1. 32), the three angles of the triangle CAB, namely, the angles CAB, ABC, BCA, are equal to two right... ## The First Six and the Eleventh and Twelfth Books of Euclid's Elements: With ...

Euclid - Geometry - 1837 - 410 pages
...XXII. THEOR. THE opposite angles of any quadrilateral figure described in a circle, t are together equal to two right angles. Let ABCD be a quadrilateral...are together equal to two right angles. Join AC, BD. Then (III. 21.) the angles CAB.CDB are equal, because they are in the same segment BADC; and the angles... ## Elements of Geometry: Containing the First Six Books of Euclid : with a ...

John Playfair - Geometry - 1837 - 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...are together equal to two right angles. Join AC, BD. The angle CAB is equal (21. 3.) to the angle CDB, because they are in the same segment BADC, and the... 