 | Edinburgh univ - 1871 - 392 sider
...described upon the other two sides of it, the angle contained by these two sides is a right angle. 3. If a straight line touch a circle, and from the point...the circle, the angles made by this line with the tangent are equal to the angles in the alternate segments of the circle. 4. To describe an isosceles... | |
 | Henry William Watson - 1871 - 320 sider
...triangles are equal in all respects, therefore DE is equal to DF, and ADE is equal to ADF. PROPOSITION 2I. If a straight line touch a circle and from the point of contact another straight line be drawn cutting the circle, the angles which the cutting line makes with the... | |
 | Euclides, James Hamblin Smith - 1872 - 376 sider
...are normals to the circle at the points where they meet the circumference. PROPOSITION 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 must be in that line. Let the st. line... | |
 | Euclides - 1872 - 102 sider
...circles touched by both lines lie in two lines at right angles to each other. PROPOSITION XIX. THEOREM. If a straight line touch a circle, and from the point of contact a straight line be draicn at right angles to the touching line, the centre of the circle must be in that line. Let the... | |
 | Henry Major - 1873 - 588 sider
...is equal to the same two ; and when the adjacent angles are equal, they are right angles. XXXII. — If a straight line touch a circle, and from the point of contact a straight line lie drawn meeting the circle, the angles which this line makes with the line touching the circle shall... | |
 | Euclides - 1874 - 342 sider
...is, 5. FC is perpendicular to DE. Therefore, if a straight line, &c. QED PROPOSITION 19.— 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... | |
 | Francis Cuthbertson - 1874 - 400 sider
...(111.15) but L ABP is < a right / ; ANGLES IN CIRCLES. PROPOSITION XVII. 119 If a straight line touches a circle, and from the point of contact a straight line be drawn cutting the circle; the angles which this straight line makes with the tangent shall be equal h the angles in the alternate segments... | |
 | Edward Atkins - 1874 - 428 sider
...perpendicular to DE, but FC; therefore FC is perpendicular to DE. PROPOSITIONS. Proposition 19.— 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... | |
 | Braithwaite Arnett - 1874 - 130 sider
...double of the square on half the line, and of the square on the line between the points of section. 4. 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. Describe a circle... | |
 | Bombay city, univ - 1874 - 648 sider
...meeting in F the lino CF which bisects the angle between CD and BC produced : prove that AE = EF. 3. If a straight line touch a circle and from the point of 8 contact a straight line bo drawn cutting the circle, the angles which this line makes with the line... | |
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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. 
