When a straight line set up on a straight line makes the adjacent angles equal to one another, each of the equal angles is right, and the straight line standing on the other is called a perpendicular to that on which it stands. Introduction and books 1,2 - Page 181by Euclid, Sir Thomas Little Heath, Johan Ludvig Heiberg - 1908Full view - About this book
| Euclides - 1863
...Therefore the angle ADG is equal (I. 8) to the angle GDB. But when a straight line standing upon another **straight line makes the adjacent angles equal to one another, each of** these angles is a right angle (I. Def. 10). Therefore the angle GDB is a right angle. But FDB is likewise... | |
| Euclides - 1864
...therefore the angle A FE is equal to the angle BFE; (I. 8.) 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; (i. def. 10.) therefore each of the angles AFE, BFE, is a right angle : wherefore... | |
| Euclides - 1865
...is equal to the angle CHG; (i. 8) 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... | |
| Robert Potts - Mathematics - 1865 - 504 pages
...therefore the angle AFE is equal to the angle BFE; (i. 8.) 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 ; (i. def. 10.) therefore each of the angles AFE, BFE, is a right angle : wherefore... | |
| Edward Clarke Lowe - 1866
...meet together, but are not in the same straight line. 10. When a straight line standing on another **straight line makes the adjacent angles equal to one another, each of** these angles is called a right angle; and the straight line which stands on the other is & perpendicular... | |
| Isaac Todhunter - Euclid's Elements - 1867 - 400 pages
...therefore the angle AFE is equal to the angle BFE. [I. 8. But when a straight line, standing on another **straight line, makes the adjacent angles equal to one another, each of the** angles is called a right angle ; [I. Definition 10. therefore each of the angles AFE, BFE is a right... | |
| Robert Potts - Mathematics - 1868 - 410 pages
...therefore the angle AFE is equal to the angle BFE; (I. 8.) 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; (I. def. 10.) therefore each of the angles AFE, BFE, is a right angle : wherefore... | |
| Edward Morris Reynolds - Geometry - 1868 - 112 pages
...angle stands alone one letter only is often used, as A. When one straight line standing on another **straight line makes the adjacent angles equal to one another, each of** these angles is called a right angle; and the straight line which stands on the other is said to be... | |
| Isaac Todhunter - 1869
...another angle, or four times another angle ; and so on. 8. When a straight line standing on another **straight line makes the adjacent angles equal to one another, each of the** angles is called a right angle, and the straight line which stands on the other is called a perpendicular... | |
| Alfred Hiley - 1871
...AC, but upon the extent or opening between the lines. XI. When a straight line standing upon another **straight line makes the adjacent angles equal to one another, each of** them is called a right A angle ; and the straight line standing upon the other is called a perpendicular... | |
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