If a straight line touch a circle, and from the point of contact a straight line be drawn cutting the circle, the angles which this line makes with the line touching the circle, shall be equal to the angles which are in the alternate segments of the circle. The Elements of Geometry, Symbolically Arranged - Page 79by Great Britain. Admiralty - 1846Full view - About this book
| Euclides - Geometry - 1853 - 334 pages
...touching lines are right angles, and therefore equal : which is impossible (Az. 9). PBOP. XIX. THEOE. If a straight line touch a circle, and from the point of contact a straight line be drawn at right angles to it : then the centre of the circle shall be in that line. Let DE touch the circle... | |
| Euclides - 1853 - 146 pages
...FC; that is 5. FC is perpendicular to DE. Therefore, if a straight line, &c. QED PROP. XIX. THEOREM. 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 shall be in that line. Let the straight... | |
| Royal Military Academy, Woolwich - Mathematics - 1853 - 400 pages
...that is, FC is perpendicular to DE. Therefore, if a straight line, etc. QED PROPOSITION 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 shall be in that line. Let the straight... | |
| Euclid - Geometry - 1853 - 176 pages
...part ff the circumference for its base as an angle at the circumference. If a straight line touches a circle, and from the point of contact a straight line be drawn cutting the circle. They shall stand upon equal parts of the circumference, whether they be at the center or the circumfer... | |
| Euclides - Geometry - 1853 - 178 pages
...e. Therefore, if a straight line, &c. QED PROPOSITION XIX. — THEOREM. 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... | |
| William Somerville Orr - Science - 1854 - 534 pages
...here only to avoid interruption in the numbering of the propositions. PROPOSITION XIX.— THEOREM. If a straight line touch a circle, and from the point of contact a straight line be draw» at right angles to the touching line, the centre of the circle shall be in that. lim. PROPOSITION... | |
| John Playfair - Geometry - 1855 - 334 pages
...; and when the adjacent angles are equal, they are right anles. •T*"*'V i^ PROP. XXXII. THEOR. Jf a straight line touch a circle, and from the point...straight line be drawn cutting the circle, the angles made by this line with the lute which touches the circle, shall be equal to the angles in the alternate... | |
| Robert Potts - 1855 - 1050 pages
...as c is the Arithmetic, Geometric, or Harmonic mean between a and b. 6. If a straight line touches a circle, and from the point of contact a straight line be drawn cutting the circle, the angles made by this line with the line touching the circle, shall be equal to the angles which are in the... | |
| Euclides - 1855 - 262 pages
...extremities, without producing it, by means of the first part of this proposition. PROP. XXXII. THE 0 В. E M. If a straight line touch a circle, and from the point of contact a straight line bе drawn cutting the circle • the. angles which this straight line makes with the tangent are equal... | |
| Cambridge univ, exam. papers - 1856 - 252 pages
...line which joins their centres shall pass through the point of contact. 10. If a straight line touches a circle, and from the point of contact a straight...which are in the alternate segments of the circle. 11. Upon a given straight line to describe a segment of a circle which shall contain an angle equal... | |
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