| Euclides - 1855
...assumed the truth of this proposition, and it seems almost impossible to do otherwise. PROP. IV. THEOREM. **If a straight line stand at right angles to each of two straight lines at** the point of their intersection, it is at rigid angles to the plane in, which they arc. Let the straight... | |
| Euclides - 1855
...AF is perpendicular to DE; therefore AF is perpendicular to each of the straight lines GH, DE. But **if a straight line stand at right angles to each of two straight lines** in the point of their intersection, it is also at right angles to the plane passing through them (d):... | |
| George Roberts Perkins - Geometry - 1856 - 460 pages
...intersection of the two planes is in a straight line. THEOREM Iv. If a straight line is perpendicular **to each of two straight lines at their point of intersection^ it** is perpendicular to the plane of these lines. Let AP be perpendicular to the two lines PB, PC, at their... | |
| 1858
...between its points of contact is a mean proportional between the diameters. BOOK XI. 10. PROP. IV. — **If a straight line stand at right angles to each of two straight lines** in the point of their intersection, it shall also be at right angles to the plane which passes through... | |
| Great Britain. Parliament. House of Commons - Bills, Legislative - 1858 - 690 pages
...between its points of contact is a mean proportional between the diameters. BOOK XI. 10. PROP. IV. — **If a straight line stand at right angles to each of two straight lines** in the point of their intersection, it shall also be at right angles to the plane which passes through... | |
| Elias Loomis - Conic sections - 1858 - 234 pages
...common section. Hence, if two planes, &c. PROPOSITION IV. THEOREM. If a straight line be perpendicular **to each of two straight lines at their point of intersection, it will** be perpendicular to the plane in which these lines are. Let the straight line AB be perpendicular to... | |
| Civil service - 366 pages
...between its .points of contact is a mean proportional between the diameters. BOOE XI. PROP. IV.— **If a straight line stand at right angles to each of two straight lines** in the point of their intersection, it shall also be at right angles to the plane which passes through... | |
| Joseph Charles Parkinson - 1860
...between its points of contact is a mean proportional between the diameters. BOOK XI. 10. PROP. IV. — **If a straight line stand at right angles to each of two straight lines** in the point of their intersection, it shall also be at right angles to the plane which passes through... | |
| Eucleides - 1860 - 396 pages
...AF is perpendicular to DE ; therefore AF is perpendicular to each of the straight lines GH, DE. But **if a straight line stand at right angles to each of two straight lines** in the point of their intersection, it is also at right angles to the plane passing through them (d)... | |
| George Roberts Perkins - Geometry - 1860 - 443 pages
...intersection of the two planes is in a straight line. THEOREM IV. If a straight line is perpendicular **to each of two straight lines at their point of intersection, it** is perpendicular to the plane of these lines. Let AP be perpendicular to the two* lines PB, PC, at... | |
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