 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.  A course of geometrical drawing - Page 2by William Schofield Binns - 1861Full view - About this book
 | Thomas Curtis - Aeronautics - 1829 - 814 pages
...that form the angle, thus С ü D or D В С denotes the angle contained by the line С В and DB. 7. When a straight line standing on another straight...which stands on the other is called a PERPENDICULAR. Fig. 4. 8. An OBTUSE ANGLE is that which is greater than a right angle. Fig. 5. 9. An ACUTE ANGLE is... | |
 | John Playfair - Geometry - 1829 - 186 pages
...When a straight line standing on another straight line makes the adjacent angles equal to each other, each of the angles is called a right angle; and the...stands on the other is called a perpendicular to it. Otherwise. When a straight line standing on another straight line does not incline to either side of... | |
 | James Charlton - Geography - 1829 - 250 pages
....,; . l 5tn"A f itei,*& i theinc!ination or opening -of two angles is called a RIGHT ANGLE ; and the line which stands on the other, is called a PERPENDICULAR to it. •• • > i •••••• i OF THE TERRESTRIAL •'CLdME.'"' 28. The TERRESTRIAL GLOBE is an... | |
 | Thomas Perronet Thompson - Euclid's Elements - 1833 - 150 pages
...equivalent. But whenever the contrary is not expressed, it is always the direct angle that is meant. XXXVII. When a straight line standing on another straight...stands on the other is called a perpendicular to it ; and is also said to be at right angles to it. XXXVIII. An angle greater than a right angle, is called... | |
 | Euclid - Euclid's Elements - 1833 - 183 pages
...(ABC and ABD) equal to one another, each of these angles is called a right angle ; B and the right line, which stands on the other, is called a perpendicular to it. Fig. 1. 12. The angle (ABC), which is greater than a right angle, is called obtuse. Fig. 4. 13. The... | |
 | Euclid - 1835 - 540 pages
...the angle at E.' X. When a straight line standing on another straight line makes the adja- • cent angles equal to one another, each of the angles is...stands on the other is called a perpendicular to it XI. An obtuse angle is that which is greater than a right angle. XII. An acute angle is that which... | |
 | Mathematics - 1836 - 472 pages
...of two straight lines to one another, which meet together but are not in the same straight line. 7. When a straight line standing on another straight...stands on the other is called a perpendicular to it. 8. An obtuse angle is that which is greater than a right angle. 9. An acute angle is that which is... | |
 | John Playfair - Euclid's Elements - 1836 - 488 pages
...a straight line standing on another straight line makes the adjacent angles equal to one an, other, each of the angles is called a right angle; and the straight line which stands on the other ie called a perpendicular to it. , VIII. An obtuse angle is that which is greater than a right angle.... | |
 | Euclid - Geometry - 1837 - 410 pages
...meet one another.^ The point in which the straight lines meet is called the vertex of the angle. 8. When a straight line standing on another straight...stands on the other is called a perpendicular to it, and is said to be at right angles to it. 9. An obtuse angle is that / which is greater than a right... | |
 | James Thomson (LL.D.) - Arithmetic - 1837 - 294 pages
...When one straight line standing on another, makes with it two angles which are equal, each of these angles is called a RIGHT ANGLE ; and the straight line which stands on the other is said to be PERPENDICULAR, Or AT RIGHT ANGLES, tO it, or tO be a PERPENDICULAR to it. III. An OBTUSE... | |
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