 | Sir Henry Edward Landor Thuillier - Surveying - 1851 - 826 pages
...another, which meet together, but are not in the same straight line.* 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... | |
 | Euclides - 1852 - 152 pages
...contained by BD, 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 E." [Observe that BAC is a greater angle than DEF, because the inclination of BA to AC is greater than... | |
 | Euclides - Geometry - 1853 - 176 pages
...С b, is called the angle db С, ог С bd ; 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. X. When a straight line standing on another straight line makes the adjacent angles equal to one another,... | |
 | Euclides - 1853 - 146 pages
...contained by SB, 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 E." x. When a straight line standing on another straight line makes the adjacent angles equal to one another,... | |
 | Royal Military Academy, Woolwich - Mathematics - 1853 - 400 pages
...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 E. 10. When a straight line standing on another straight line makes the adjacent angles equal to one another,... | |
 | John Playfair - Geometry - 1855 - 334 pages
...' BD, CB, is called the angle DBC, or CBD ; but, if there be only one an' gle at a point, it may be expressed by a letter placed at that point; as the ' angle at £.' 7. When a straight line standing on another straight line makes the adjacent angles equal to one... | |
 | Euclides - 1856 - 168 pages
...on the point of intersection between the straight lines or arms of the angle. XV. — RIGHT ANGLE. When a straight line standing on another straight line makes the adjacent angles equal to each other, each of the angles is called a right angle, and the straight line which stands on the other... | |
 | Robert Rawson - 1856 - 178 pages
...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 E." When a straight line standing on another straight line makes the adjacent angles equal to one another,... | |
 | William Ezra Worthen - Architectural drawing - 1857 - 650 pages
...only one angle at a point, it may be expressed by a letter placed at that point ; as the angle at E.' 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 lines are said to be perpendicular to each other... | |
 | W.E. WORTHEN - 1857 - 600 pages
...lines, AB, CB, is named the angle ABO, or CBA; 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.' When a straight line standing on another straight line makes the adjacent angles equal to one another,... | |
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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. 
