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
| Euclides - 1879
...the lines meet is often called the vertex of the angle.] 10. When a straight line standing on another **straight line makes the adjacent angles equal to one another, each of** these angles is called a right angle ; and the straight line which stands on the other is called a... | |
| 1880
...DEFINITION OF RIGHT ANGLES. JTigr.J. Euc. Def. io.) — 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 -A. -0 .* said... | |
| Isaac Todhunter - Euclid's Elements - 1880 - 400 pages
...therefore the angle ADG is equal to the angle BDG. [I. 8. 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 ; [I. Definition 10. therefore the angle BDG is a right angle. But the... | |
| Marianne Nops - 1882
...acutus, sharp). These are thus defined by Euclid : — 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... | |
| A J G. Barclay - 1883 - 96 pages
...and .-. L DCF = L ECF, and these 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. .-. CF is at right angles to AB, and is drawn from the given point... | |
| Euclid's Elements - 1883 - 400 pages
...therefore the angle AFE is equal to the angle BFE. [I. 8. 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 ; [I. Definition 10. therefore each of the angles AFE, BFE is a right... | |
| 1884
...therefore the angle CHF is equal to CHG ; and they are adjacent angles ; but when a straight line 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... | |
| 1884
...is equal to the angle ; and these are adjacent angles. But when a straight line standing on another **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... | |
| 1884
...standing on another straight line makes the adjacent angles equal, each of them is called a Right Angle ; **and the straight line standing on the other is called a Perpendicular,** or said to be at right angles to it. (5) A Square is a four-sided figure, having all its sides equal... | |
| 1884
...of proof. The definition of a right angle is as follows : " When a straight bine standing on another **straight line makes the adjacent angles equal to one another, each of** these angles is called a right angle ; and the straight line which stands on the other is called a... | |
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