 | Euclides - 1864 - 448 pagina’s
...together, but are not in the same straight line. I) NB If there be only one angle at a point, it may be expressed by a letter placed at that point, as the angle at E : but when several angles are at one point B, either of them is expressed by three letters, of which... | |
 | Euclides - 1865 - 80 pagina’s
...lines which meet in a point, called the vertex of an angle, and the two lines are called its sides. 9. When a straight line standing on another straight line makes the adjacent angles equal, each of them is called a RIGHT ANGLE; and the straight line which stands upon the other is called a... | |
 | Robert Potts - 1865 - 528 pagina’s
...together, but are not iii the same straight line. D XB If there be only one angle at a point, it may be expressed by a letter placed at that point, as the angle at E : but when several angles are at one point B, either of them is expressed by three letters, of which... | |
 | Euclides - 1865 - 402 pagina’s
...by DB, CB, is called the angle DBC, or CBD ; but, if there be only one angle at a point, it may be expressed by a letter placed at that point : as the angle at !•'.. X. When a straight line standing on another straight line makes the adjacent angles equal to... | |
 | William Harris Johnston - 1865 - 478 pagina’s
...other angle between them, such as the angles ВАС and DA 0. When one straight line standing upon another straight line makes the adjacent angles equal to one another, each such angle is called a right angle, and either of the straight lines is said to be a perpendicular... | |
 | George Frederick Chambers - 1867 - 888 pagina’s
...lines to each other in the same plane gives rise to a plant rectilineal angle, or simply an angle. When a straight line, standing on another straight line, makes the adjacent angles equal to each other, each of those angles is called a right angle; but if the adjacent angles are not equal... | |
 | Euclid, Isaac Todhunter - 1867 - 424 pagina’s
...lines DB, CB is named the angle DBC, or CBD • but if there be only one angle at a point, it may be expressed by a letter placed at that point; as the angle at E. 10. When a straight line standing on another straight line, makes the adjacent angles equal to one... | |
 | Euclid, Isaac Todhunter - 1867 - 426 pagina’s
...lines DB, CB is named the angle DBC, or CBD ; but if there be only one angle at a point, it may be expressed by a letter placed at that point; as the angle at E. 10. When a straight line standing on another straight line, makes the adjacent angles equal to one... | |
 | Robert Potts - 1868 - 434 pagina’s
...together, but are not in the same straight line. g, NB If there be only one angle at a point, it may be expressed by a letter placed at that point, as the angle at E : but when several angles are at one point B, either of them is expressed by three letters, of which... | |
 | Isaac Todhunter - 1869 - 312 pagina’s
...statement that a certain angle is three times another angle, or four times another angle ; and so on. 8. When a straight line standing on another straight...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... | |
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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 to it. 
