When a straight line set up on a straight line makes the adjacent angles equal to one another, each of the equal angles is right, and the straight line standing on the other is called a perpendicular to that on which it stands. Introduction and books 1,2 - Page 181by Euclid, Sir Thomas Little Heath, Johan Ludvig Heiberg - 1908Full view - About this book
| John Keill - Geometry - 1723 - 364 pages
...the Angle AFE j. g ti fhall bef equal to the Angle BFE. But when a Right Line {landing upon a Right **Line makes the adjacent Angles equal to one another, each of the equal Angles is** ia Right Angle. Wherefore AFE, or BFE, is a Right Angle. And therefore the Right Line CD drawn thro*... | |
| Euclid, John Keill - Geometry - 1733 - 393 pages
...Therefore the Angle * 8- i. AD G is * equal to the Angle GD B. But when a Right Line ftanding upon 'a Right **Line, makes the adjacent Angles equal to one another, each of the** 10. i. equal Angles will f be a Right Angle. Wherefore the Angle GDB is a Right Angle. But FDB is alfo... | |
| Robert Simson - Trigonometry - 1762 - 466 pages
...the angle ADG is equal c to the angle GDB. but when a ftraight line ftanding upon another ftraight **line, makes the adjacent angles equal to one another ,each of the** angles is a right angle *. therefore the angle GDB is a right angle. but FDB is like- d.io.Def.i. wife... | |
| Euclid - Geometry - 1765 - 464 pages
...angle EH c [by prop. 8.] ; and thefe are adjacent angles. But when a right line flanding upon a right **line makes the adjacent angles equal to one another, each of the equal angles is** a right angle, and the ftanding right line is called a perpendicular to that upon which it Sands. tar... | |
| John Keill - Geometry - 1772 - 399 pages
...the Angle AFE fliall be f equal to the Angle BFE. But when af 8. t. Right Line Standing upon a Right **Line makes the adjacent Angles equal to one another, each of the equal Angles is** J a Right Angle. Wherefore AFE, orJ0«/. 10. i« BFE, is a Right Angle. And therefore the Right •Line... | |
| Robert Simson - Trigonometry - 1775 - 520 pages
...placed at that point; « as the angle at li.' X. When a ftraight line flanding on another ftraight **line makes the adjacent angles equal to one another, each of the** angles is called a right angle ; and the ftraight line which flands on the other is called a perpendicular... | |
| James Williamson - Mathematics - 1781
...8. i.) the angle AFE is equal to the angle BFE : but when a ftraight line ftanding upon a ftraight **line makes the adjacent angles equal to one another, each of the equal angles is** a right angle ; therefore each of the angles AFE, BFE is a right angle : therefore CD through the center... | |
| Euclid - 1781 - 520 pages
...'letter placed at that point; as the Angle at E.' .X. When a ftraight line flanding on another ftraight **line makes the adjacent angles equal to one another, each of the** angles is called a right angle ; and the ftraight line which ftands on the other is called a perpendicular... | |
| John Keill - Geometry - 1782 - 399 pages
...Therefore the Angle ADG is * equal to the Angle GD B. But when 3*8.,. Right Line ftandmg upon a Right **Line makes the adjacent Angles equal to one another, each of the equal Angles** will f be a Right Angle. Wherefore fZ?»/.io.» F the the Angle GDB is a Right Angle. But FDB is alfo... | |
| Thomas Beddoes - Greek language - 1793 - 172 pages
...whether they are plane or otherwife. DEFINITION X, When a Jlfaight line ftanding on another Jiraight **line makes the adjacent angles equal to one another, each of the** angles is called a right angle, and the line which Jlands on the other is called a perpendicular to... | |
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