| David Steel - History - 1805 - 392 pages
...each other. When a straight line AD standing upon another CB, makes angles ADC, ADB, on each side, **equal to one another; each of these angles is called a Right Angle; and** C J> B the line AD is said to be Perpendicular to the line CB. An angle is usually expressed by three... | |
| John Playfair - Mathematics - 1806 - 320 pages
...at a point, it may be expressed ' by a letter placed at that point ; as the angle at E.' VII. 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... | |
| Robert Simson - Trigonometry - 1806 - 548 pages
...G * : therefore the angle ADG is equal c to the angle GDB : 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 d : therefore the angle GDB is a right angle: but FDB is likewise a '"... | |
| Euclid - Geometry - 1810 - 554 pages
...equal e to the angle CHG; and 1. they are adjacent angles; but when a straight line standing on ae 8. 1 **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... | |
| John Mason Good - 1813 - 714 pages
...straight lines to or.e another, which meet together, but are not in the same straight line. 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... | |
| George Adams - Geometry - 1813 - 576 pages
...straight line AB, //<>-. 1 , plate 4, standing upon another CD, makes angles ABC, ABD, on each side **equal to one another ; each of these angles is called a right angle ; and the** line AB is said to be perpendicular to the line CD. It is usual to express an angle by three letters,... | |
| Euclides - 1814 - 560 pages
...angle at a point, it may be ex' pressed 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, each of** the angles is called a right angle; and the straight line which stands on the other is called a perpendicular... | |
| Euclides - 1816 - 592 pages
...centre G*: Therefore the angle ADG is equal0 to the angle GDB : 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 d: Therefore the angle GDB is a right angle: MoDef. ' But FDB is likewise... | |
| John Playfair - Circle-squaring - 1819 - 348 pages
...at a point, it may be expressed by a letter placed at that point ; a&.the angle at E.' VII. 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... | |
| John Playfair - 1819 - 354 pages
...equal (8. 1.) to the angle CHG ; and thry are adjacent angles ; now when a straight lina 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... | |
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