 | Isaac Todhunter - 1869 - 312 sider
...three times another angle, or four times another angle ; and so on. 8. When a straight line standing on another straight line makes the adjacent angles equal...and the straight line which stands on the other is called a perpendicular to it. Thus, in the figure, if the angle ABC is equal to the angle ABD each... | |
 | Euclides - 1871 - 136 sider
...the definition. IX. When a straight line (as AS) meeting another straight line (as CD) makes the A adjacent angles equal to one another, each of the angles is called a RIGHT ANGLE; and each line is said to be a PEEPENDICULAB to the other. c X. An OBTUSE ANGLE is one which is greater... | |
 | Alfred Hiley - 1871 - 184 sider
...sides AB, AC, but upon the extent or opening between the lines. XI. When a straight line standing upon another straight line makes the adjacent angles equal to one another, each of them is called a right A angle ; and the straight line standing upon the other is called a perpendicular... | |
 | Elias Loomis - 1871 - 302 sider
...the angle ECD is the difiei ence 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... | |
 | Euclides, James Hamblin Smith - 1872 - 376 sider
...extension of the definition. IX. When a straight line (as AB) meeting another straight line (as CD) makes the adjacent angles equal to one another, each of the angles is called a EIGHT ANGLE; and each line is said to be a PER. _^_ PENDICULAR to the other. X. An OBTUSE ANGLE is... | |
 | William Alexander Myers - 1873 - 238 sider
...concentric circles ; *that is, having a common center, as at F. 14. When a straight line standing on another straight line makes the adjacent angles equal to one another, each of the angles is a right angle, and the straight line which stands on the other is called a perpendicular to it; IKL... | |
 | Edward Atkins - 1874 - 428 sider
...may be expressed by the letter at that point, as the angle E. 10. When a straight line standing on another straight line makes the adjacent angles equal...the straight line which stands — . on the other is called a perpendicular to it. 1 1 . An obtuse angle is that which is greater than a right angle. 12.... | |
 | Euclides - 1874 - 120 sider
...equal to the angle ECF [I. 8], and they are adjacent angles. But when a straight line, standing on another straight line, makes the adjacent angles equal...another, each of the angles is called a right angle [Def. 10] ; therefore each of the angles DCF, ECF is a right angle. Therefore from the giveu point... | |
 | William Alexander Myers - 1874 - 207 sider
...concentric circles ; that is, having a common center, as at F. 14. When a straight line standing on another straight line makes the adjacent angles equal to one another, each of the angles is a right angle, and the straight line which stands on the other is called a perpendicular to it; IKL... | |
 | Francis Cuthbertson (geometer.) - 1876 - 102 sider
...Wherefore if two straight lines &c. QED RIGHT ANGLES. DEFINITION. When one straight line, standing on another straight line, makes the adjacent angles equal to one another, each of them is called a right angle ; and the straight line which stands upon the other is - said to be perpendicular... | |
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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. 
