 | Robert Simson - 1775 - 520 σελίδες
...to the angle CHG; and they are adjacent angles ; but when a ftraight line ftanding cet on a ftraight line makes the adjacent angles equal to one another, each of them is a right angle, and the ftraight line which flands upon the other is called a perpendicular to it; therefore from the given... | |
 | John McGregor (teacher of mathematics.) - 1792 - 431 σελίδες
...two, thus : ABC, or СВЛ. 11. When one ftraight line falls upon another ftraight line, fo as to make the adjacent angles equal to one another, each of them is a right angle and the ftraight Une which falls upon the other is perpendicular to it. See plate i.fg- 4. I г. An angle which... | |
 | John Playfair - 1795 - 444 σελίδες
...the angle AFE is equal b to the angle BFE : But when a flraight line ftanding upon another nv.ik.es the adjacent angles equal to one another, each of them is a right c angle: Therefore each of the angles AFE, Bl' E is a right angle ; wherefore the ftraight line CD,... | |
 | Alexander Ingram - 1799 - 351 σελίδες
...to the angle , CHG ; and they are adjacent angles ; but when a ftraight line ftanding on a ftraight line makes the adjacent angles equal to one another, each of them is a right angle, and the ftraight line which ftands upon the other, is called a perpendicular to it ; therefore from the given... | |
 | Robert Simson - 1804
...angle CHG; and they are adjacent e. 8. i. :angles. but when a ftraight line flanding on a ftraight line makes the adjacent angles equal to one another, each of them is a right angle, and the ftraight line which ftands upon the other is called af perpen- f. to.Def.t. dicular to it. thereforefrom... | |
 | John Playfair - 1804 - 470 σελίδες
...therefore the angle AFE is equal b to the angle BFE. And when a ftraight line flanding upon another makes the adjacent angles equal to one another, each of them is a right c angle : Therefore each of the angles AFE, BFE is a right angle; wherefore the ftraight line CD, drawn... | |
 | John Playfair - 1806 - 320 σελίδες
...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... | |
 | John Mason Good - 1813 - 722 σελίδες
...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... | |
 | Euclides - 1816 - 528 σελίδες
...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 - 1819 - 317 σελίδες
...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...perpendicular to it ; therefore from the given point C a pendicular CH has been drawn to the given straight line AB. Which ivas to be done. PROP. XIII. THEOR.... | |
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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. 
