 | Robert Simson - Geometry - 1838 - 434 pages
...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... | |
 | Euclides - 1838 - 264 pages
...EB; therefore the angle AFE is equal* *si to the angle BFE: but when a straight line standing upon another straight line makes the adjacent angles equal to one another, each *s Def.i. of u,,,,,, is a right« angle. there_ fore each of the angles AFE, BFE, is a right angle:... | |
 | John Clark (drawing master.) - 1840 - 208 pages
...way. Vertical or Perpendicular Lines are those which are drawn perfectly upright. When a straight une standing on another straight line makes the adjacent angles equal to one another, then the upright une which stands on the other is called a perpendicular to it. The drawing of a perpendicular... | |
 | Euclides - Geometry - 1841 - 378 pages
...base CG; * 3. 1. therefore the angle CHF is equal* to the angle CHG; and they are adjacent angles; but when a straight line standing on another straight...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... | |
 | Euclides - 1842 - 316 pages
...CG ; therefore the angle c HF is equal (8. 1.) to the angle c н G ; and they are adjacent angles : but when a straight line standing on another straight...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... | |
 | John Playfair - Euclid's Elements - 1842 - 332 pages
...equal (8. 1.) to the angle CHG ; and they are adjacent angles ; now 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... | |
 | William Pease - Geometry - 1843 - 80 pages
...that which is formed on the surface of a sphere, by the intersection of two of its great circles. X. When a straight line standing on another straight...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. Beginners are apt... | |
 | Philip Kelland - Algebra - 1843 - 168 pages
...centre is the angular point, as trigonometers often make it. 7. When a straight line standing on another 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. By looking over... | |
 | Scottish school-book assoc - 1845 - 444 pages
...» only one angle at the point, as at E, it may be called simply the »ngle at E, PLANE GEOMETRY. 9. When a straight line standing on another straight...another, each of the angles is called a right angle; and the strnight line which stands on the other is called a perpendicular to it. 10. An obtuse angle... | |
 | Euclides - 1845 - 546 pages
...be only one angle at a point, it may be expressed by the letter at that point; as the angle at /.'. When a straight line standing on another straight line makes the adjacent angles equal to each other, each of these angles is called a right angle ; and the straight line which stands on the... | |
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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. 
