 | Euclides - 1816 - 588 pagine
...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 - 1819 - 350 pagine
...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 Playfair - 1819 - 354 pagine
...they are right angles. PROP. XXXII. THEOR. ."-> If a straight line touch a circle, and from the pbitit of contact a straight line be drawn cutting the circle, the angles made fry this line with the line which touches the circle, shall be equal to the angles in the alternate... | |
 | John Mason Good - 1819 - 800 pagine
...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 - 1825 - 1046 pagine
...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 - 1827 - 546 pagine
...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 - 1829 - 210 pagine
...to DE; therefore FC is 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 - 1830 - 584 pagine
...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 - 1833 - 346 pagine
...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... | |
 | John Playfair - 1835 - 336 pagine
...to the same two ; and 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 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 alternate segments of the circle. 
