| John Playfair - Trigonometry - 1806 - 311 pages
...is perpendicular to DE. Therefore, if a straight line, &c. QED a 17. 1. b 19. i. PROP. XIX. THEOR. **IF a straight line touch a circle, and from the point of contact a straight line be drawn** at right angles to the touching line, the centre of the circle is in that line. Book III. Let the straight... | |
| Euclid, Robert Simson - Euclid's Elements - 1806 - 518 pages
...perpendicular to DE. Therefore, if a straight line, 6cc. QED PROP. XIX. THEOR. IF a straight line touches **a circle, and from the point of contact a straight line be drawn** at right angles to the touching line, the centre of the circle shall be in that line. if possible,... | |
| Euclid - Geometry - 1810 - 518 pages
...FC is perpendicular to DE. Therefore, if a straight line, &c. QED C GE a 18. 3. ,' PROP. XIX. THEOR. **IF a straight line touch a circle, and from the point of contact a straight line be drawn** at right angles to the touching lirie, the centre of the circle shall be in that line. Let the straight... | |
| John Mason Good, Olinthus Gilbert Gregory - 1813
...shall be perpendicular to the line touching the circle. Prop. XIX. Theor. If a straight line touches **a circle, and from the point of contact a straight line be drawn** at right angles to the. touching line, the centro of the circle shall be in that line. Prop. XX. Theor.... | |
| Charles Butler - Mathematics - 1814
...demonstration, that these three perpendiculars BE, GF, and CD intersect each other in the same point AQED 249. **If a straight line touch a circle, and from the point of contact** two chords be drawn, and if from the extremity of one of them, a straight line be drawn parallel to... | |
| Peter Fleming - Surveying - 1815 - 164 pages
...ībid. 95 26 ibid, 27 28 29 - 30 ibid. 31 ibid. 33 ibid. Page Theorem 13. If a straight line touches **a circle, and from the point of contact, a straight line be drawn, cutting the circle,** the angle made by this line with the first line, shall be equal to the angle in the alternate segment... | |
| Euclides - Geometry - 1816 - 528 pages
...perpendicular to DE. Therefore if a straight , . line^&c. QED D" c PROP. XIX. THEOR. IF a straight line touches **a circle, and from the point of contact a straight line be drawn** at right angles to the touching line, the centre of the circle shall be in that line. Let the straight... | |
| John Playfair - Trigonometry - 1819 - 333 pages
...DE ; FC is therefore perpendicular to DE. Therefore, if a straight line, &c. Q, ED PROP. XIX. THEOR. **If a straight line touch a circle, and from the point of contact a straight line be drawn** at right angles to the touching line, the centre of the circle, is in that line. Let the straight line... | |
| John Mason Good, Olinthus Gilbert Gregory - 1819
...shall be perpendicular tu the line touching the circle. Prop. XIX. Theor. If a straight line touches л **circle, and from the point of contact a straight line be drawn** at right angles to the touchingline, the centre of the circle shall be in that line. Prop. XX. Theor.... | |
| Peter Nicholson - Mathematics - 1825 - 372 pages
...to DE. Therefore, if a straight line, &c. QED Proposition XIX. Tliearem. If a straight line touches **a circle, and from the point of contact a straight line be drawn** at right angles to the touching line, the centre of the circle shall be in that line. Let the straight... | |
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