 | Peter Nicholson - Mathematics - 1825 - 1046 pages
...that is, FC is perpendicular 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... | |
 | Robert Simson - Trigonometry - 1827 - 546 pages
...perpendicular to I>E. Therefore, if a straight line, &c. QED PROP. XIX. THEOR. If a straight line taucJ1es 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 - Geometry - 1829 - 210 pages
...perp. to DE. Therefore, if a straight line &c. QED PROPOSITION XIX. THEOREM. If a straight line touch a circle, and from the point of contact a straight line be drawn perpendicular to the tangent, the centre of the circle is in that line. • ' N CG 1) c E Let the straight... | |
 | Pierce Morton - Geometry - 1830 - 584 pages
...the point of contact, shall be perpendicular to the line touching the circle. Cor. 2. (Eue. iii. 19.) 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. Cor. 3. Tangents... | |
 | John Playfair - Euclid's Elements - 1833 - 346 pages
...they are right angles. PROP. XXXII. THEOR. .» If a straight line touch a.circle, and from thepoint of contact a straight line be drawn cutting the circle, the angles made by this line with the line which touches the circle, shall be equal to the angles in the alternate segments of the circle. Let... | |
 | Euclides - 1834 - 518 pages
...equal, they are t right angles. f 10 Def. 1• PROPOSITION XXXII. ¥ THEOR. — 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... | |
 | Mathematics - 1835 - 684 pages
...the point of contact, shall be perpendicular to the line touching the circle. Cor. 2. (Eue. iii. 19.) 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. Cor. 3. Tangents... | |
 | Robert Simson - Trigonometry - 1835 - 544 pages
...is, FC is perpendicular to DE. tz: Therefore, " if a straight line," .i) &c. QED PROP. XIX. THEOR. If a straight line touches a circle, and from the point of contact a straight line is drawn at rig ht angles to the touching line, the centre of the circle is in that line. Let the straight... | |
 | Euclid - 1835 - 540 pages
...to the same two ; and when the adjacent angles are equal, they are right angles. PROP. XXXII. THEOR. If a straight line touches a circle, and from the point of contact a straight line is drawn cutting the circle, the angles made by this line with tJie line touching the circle, are equal... | |
 | John Playfair - Euclid's Elements - 1835 - 336 pages
...when the adjacent angles are equal, they are right angles. PROP. XXX. THEOR. If a straight line touch a circle, and from the point of contact a straight line be draion cutting the circle, the angles made by this line with the line which touches the circle, shall... | |
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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. 
