 | 1844 - عدد الصفحات: 688
...opposite angles of any quadrilateral inscribed in a circle, are together equal to two right angles. 11. If a straight line touch a circle, and from the point...circle ; the angles which this line makes with the touching line, shall be equal to the angles in the alternate segments. 12. If two triangles have one... | |
 | John Playfair - 1844 - عدد الصفحات: 338
...be perpendicular to DE ; FC is therefore perpendicular to DE. PROP. XIX. THEOR. If a straight lino 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... | |
 | Euclid, James Thomson - 1845 - عدد الصفحات: 382
...semicircle is acute, and an angle ma segment less than a semicircle is obtuse. PROP. XXXII. THEOR. — If a straight line touch a circle, and from the point of contact a straight line be drawn dividing the circle into two segments ; the angles made by this line with the tangent are equal to... | |
 | Euclid - 1845 - عدد الصفحات: 218
...that is, FC is perpendicular to DE. Therefore, if a straight line, &c. QED PROPOSITION XIX. THEOB. — 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... | |
 | Euclides - 1845 - عدد الصفحات: 546
...to DE. Therefore, if a straight line, &c. QED PROPOSITION XIX. THEOREM. // 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... | |
 | Great Britain. Admiralty - 1846 - عدد الصفحات: 128
...no other line but FC is J_ DE, ie FC J_ DE. Therefore if a str. line, &c. PROP. LIV. THEOR. 19. 3Eu. 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 str. line... | |
 | Great Britain. Admiralty - 1846 - عدد الصفحات: 128
...other line but FC is J_ DE, ie FC J_ DE. Therefore if a str. line, &c. PROP. LIV. THEOR. 19. 3E u. 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 str. line... | |
 | Euclides - 1846 - عدد الصفحات: 292
...that is, FC is perpendicular to DE. Wherefore, If a straight line %c. < i . E. 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 shall be in that line. Let the straight... | |
 | Euclid, John Playfair - 1846 - عدد الصفحات: 334
...perpendicular to DE ; FC is therefore perpendicular to DE. ELEMENTS PROP. XIX. THEOR. If a straight linf 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... | |
 | Euclides - 1848 - عدد الصفحات: 52
...or in the circumference, which shall touch a given circle. PROP. XVIII. THEOREM. 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. PROP. XX. THEOREM.... | |
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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. 
