| Euclides - 1834 - 518 σελίδες
...base EB ; therefore the angle AFE is equal* to the angle BFE : but when a straight line, standing upon another straight line, makes the adjacent angles equal to one another, each of them is a right* angle; therefore each of the angles AFE, BFE is a right angle : wherefore the straight... | |
| 1835 - 684 σελίδες
...letter, as A, always denotes the angular point. 10. (Eue. i. det 10.) When a straight line standing; upon another straight line makes the adjacent angles equal to one another, each of them is called a right angle, and the straight line which stands upon the other is called a perpendicular... | |
| Euclid - 1835 - 540 σελίδες
...is equal" to the angle CHG ; and they are adjacent angles ; but when a straight line standing on a straight line makes the adjacent angles equal to one another, each of them is a right angle ; and the straight line which stands upon the other is called a perpendicular... | |
| 1836 - 488 σελίδες
...another, which meet together but are not in the same straight line. 7. When a straight line standing on another straight line makes the adjacent angles equal...and the straight line which stands on the other is called a perpendicular to it. 8. An obtuse angle is that which is greater than a right angle. 9. An... | |
| John Playfair - 1836 - 488 σελίδες
...a straight line standing on another straight line makes the adjacent angles equal to one an, other, each of the angles is called a right angle; and the straight line which stands on the other ie called a perpendicular to it. , VIII. An obtuse angle is that which is greater than a right angle.... | |
| John Playfair - 1836 - 148 σελίδες
...equal (7. 1.) to the angle CHG, and they are adjacent angles ; but when a straight line, standing on a straight line, makes the adjacent angles equal to one another, each of them is a right angle, and the straight line which stands upon the other, is called a perpendicular... | |
| Euclid, James Thomson - 1837 - 410 σελίδες
...which the straight lines meet is called the vertex of the angle. 8. When a straight line standing on another straight line makes the adjacent angles equal...and the straight line which stands on the other is called a perpendicular to it, and is said to be at right angles to it. 9. An obtuse angle is that /... | |
| James Thomson (LL.D.) - 1837 - 296 σελίδες
...When one straight line standing on another, makes with it two angles which are equal, each of these angles is called a RIGHT ANGLE ; and the straight line which stands on the other is said to be PERPENDICULAR, Or AT RIGHT ANGLES, tO it, or tO be a PERPENDICULAR to it. III. An OBTUSE... | |
| John Playfair - 1837 - 332 σελίδες
...therefore the angle ADG is equal (8. 1.) to the angle GDB : But when a straight line standing upon another straight line makes the adjacent angles equal to one another, each of the angles is a right angle (7. def. i .) Therefore the angle GDB is a right angle : But FDB is likewise a right... | |
| Robert Simson - 1838 - 434 σελίδες
...equal (8. 1.) to the angle CHG; and they are adjacent angles ; but when a straight line standing on a straight line makes the adjacent angles equal to one another, each of them is a right angle, and the straight line which stands upon the other is called a perpendicular... | |
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