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 - 1849 - 226 pagesFull view - About this book
| Isaac Todhunter - Measurement - 1869 - 312 pages
...three times 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... | |
| Elias Loomis - Geometry - 1871 - 302 pages
...divided. Thus, the angle BCD is the sum of the two angles BCE, ECD ; and the angle ECD is the difiei ence **between the two angles BCD, BCE. 10. When a straight...perpendicular to it. 11. An acute angle is one which is** lew than a right angle. An obtuse angle is one which .'s greater than a right angle. 12. Parallel straight... | |
| Alfred Hiley - 1871 - 184 pages
...sides AB, 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 to it. Thus if AB,... | |
| William Alexander Myers - Circle-squaring - 1873 - 238 pages
...concentric circles ; *that is, having a common center, as at F. 14. When a straight line standing on **another straight line makes the adjacent angles equal to one another, each of** the angles is a right angle, and the straight line which stands on the other is called a perpendicular... | |
| Henry Major - Student teachers - 1873 - 588 pages
...line. An angle is named from three or one letters, as ABC or B. X. When a straight line standing oil **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... | |
| Francis Cuthbertson - Euclid's Elements - 1874 - 400 pages
...respects, and.-. AE is =BE; (i. i) ( 14 ) 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. PROPOSITION VI. If two straight lines cut... | |
| John Clement P. Aldous - 1874 - 104 pages
...There is one well-known angle by which angles may be measured. DBF. When one straight line standing on **another straight line makes the adjacent angles equal to one another, each of** these angles is called a Bight Angle. Now all right angles are equal to one another. So that any angle... | |
| Euclides - 1874 - 120 pages
...equal to the angle CHG [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 called a right angle, and the 'straight line which stands on the other is called a perpendicular... | |
| Euclides - 1874 - 342 pages
...therefore 1. The cmgle ADG is equal to the angle GDB (I. 8), but when a straight line standing upon **another straight line makes the adjacent angles equal to one another, each of** the angles is a right angle (I. Def. 10) ; therefore 2. The angle GDB is a right angle ; but FDB is... | |
| William Alexander Myers - Circle-squaring - 1874 - 207 pages
...concentric circles ; that is, having a common center, as at F. 14. When a straight line standing on **another straight line makes the adjacent angles equal to one another, each of** the angles is a right angle, and the straight line which stands on the other is called a perpendicular... | |
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