 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.  Elements of Geometry and Conic Sections - Page 10by Elias Loomis - 1857 - 226 pagesFull view - About this book
 | Euclid, James Bryce, David Munn (F.R.S.E.) - Geometry - 1874 - 236 pages
...tne lines. 8. When one straight line stands on another, so as to make the two adjacent angles equal, each of them is called a right angle; and the straight line standing on the other is said to be perpendicular or at right angles to it. Sj if the line OB, standing... | |
 | Henry Lewis (M.A.) - Measurement - 1875 - 104 pages
...angle," but it is, perhaps, a little too difficult for beginners: — 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. An acute angle is less than a right angle, as ABD, DEE. An obtuse... | |
 | Francis Cuthbertson (geometer.) - 1876 - 102 pages
...Wherefore if two straight lines &c. QED RIGHT ANGLES. DEFINITION. When one straight line, standing on another straight line, makes the adjacent angles equal...called a right angle ; and the straight line which stands upon the other is - said to be perpendicular to it. EUCLID'S AXIOM. — All right angles are... | |
 | Richard Wormell - 1876 - 268 pages
...common vertex, and are on opposite sides of a common side. 1 8. 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... | |
 | George Elliot Voyle, G. de Saint-Clair-Stevenson - English language - 1876 - 676 pages
...applied to substantive rank (viile Rank) in the army. Perpendicular — When a straight line standing on another straight line makes the adjacent angles equal to one another, each of these angles is a right angle, and the line perpendicular. Persian Wheel — A contrivance for raising... | |
 | Robert Potts - Geometry - 1876 - 446 pages
...which is contained by DB. CB, is called the angle DBC, or CUD. X. 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 called a... | |
 | Edward Atkins - 1876 - 130 pages
...equal to the angle EOF (I. 8) ; And they are adjacent angles. But when a straight line, standing on another straight line, makes the adjacent angles equal to one another, each of the angles is callccl a. right angle (Def. 10) ; AD = Make CE = CD nnj A DBF equilatcral. * EC*' .... | |
 | Isaac Todhunter - Philosophy - 1877 - 452 pages
...other. This is put into a more precise form in the following manner: 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... | |
 | Euclides - 1877 - 58 pages
...to the angle ECF ; (prop. 8) and they are adjacent angles : but " 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 ; " (def. 9) therefore each of the angles DCF, ECF is a right... | |
 | Edward Atkins - 1877 - 72 pages
...may be expressed by the letter at that point, as the angle K 10. "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... | |
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