 | William Ezra Worthen - Architectural drawing - 1857 - 632 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...equal to one another, each of the angles is called a rig fit angle ; and the straight lines are said to be perpendicular to each other (fig. 3). An obtuse... | |
 | Elias Loomis - Conic sections - 1858 - 256 pages
...the angle ECD is the difference between the two angles BCD, BCE. 10. When a straight line, meeting another straight line, makes the adjacent angles equal to one another, each of them is called a right angle, and the straight line which meets the other is called a perpendicular... | |
 | Popular educator - 1860 - 536 pages
...is equal to the base OH, and the angle CHF (I. 4) to the angle CBO ; 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... | |
 | Robert Potts - Geometry, Plane - 1860 - 380 pages
...(def. 15.) therefore the angle FHC is equal to the angle GHC; (I. 8.) and these 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... | |
 | Isaac Todhunter - 1860 - 318 pages
...meet together, but are not in the same straight line. And when a straight line standing on another makes the adjacent angles equal to one another, each of the angles is called a right angle. A right angle is divided into 90 equal parts called degrees, a degree is divided into 60 equal parts... | |
 | William Schofield Binns - 1861 - 238 pages
...inclination of two straight lines to one another, meeting or cutting each other in a point, as c (10) " 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." The angles AB c,... | |
 | Janes Boddely Keene - 1861 - 104 pages
...the angle. Plate I., Fig. 1. 10. Angles are of three kinds. Fig. 2. a. The Right Angle. — If one straight line standing on another straight line makes the adjacent angles equal to one another, each is .called a right angle, and the line standing on the other is said to be perpendicular to it. b.... | |
 | Euclides - 1862 - 140 pages
...15.) 4. Therefore the angle CHF is equal to the angle CHG (1. 8), and they are adjacent angles. 5. But 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. (def. 10.) Conclusion.... | |
 | Euclides - 1862 - 172 pages
...therefore the angle AFE is equal to the angle BFE ; (i. 8) but 'when a straight line standing upon another straight line makes the adjacent angles equal to one another, each of them is a right anele ;' therefore each of the angles AFE, BFE, is a right angle; wherefore the straight... | |
 | Euclides - 1863 - 122 pages
...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...the adjacent angles equal to one another, each of these angles is called a right angle ; and the straight line which stands on tbo other is called a... | |
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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. 
