| Mathematics - 1835 - 684 pages
...and perpendicular straight line. A straight line when said to be perpendicular to a plane , . 125 (a) **If a straight line stand at right angles to each of two** other straight lines at their point of intersection, it shall be at right angles to the plane in which... | |
| John Martin Frederick Wright - Mathematics - 1836 - 776 pages
...perpendiculars from the angular points. EUCLID, BOOK XI. 1817. 1 . DEFINE the five regular solid figures. 2. **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... | |
| Mathematics - 1836 - 488 pages
...are in one plane. III. If two planes cut one another, their common section is a straight line. IV. **If a straight line stand at right angles to each of two straight lines** in their point of intersection, it will also be at right angles to the plane in which these lines are.... | |
| A. Bell - Conic sections - 1837 - 180 pages
...common to the planes AB and BC, or it is the common section of these planes. PROPOSITION IV. THEOREM. **If a straight line stand at right angles to each of two straight lines** in the point of their intersection, it will also be at right angles to the plane in which these lines... | |
| Euclid, James Thomson - Geometry - 1837 - 410 pages
...straight line.* Therefore, if two planes, &c. PROP. IV. THEOR. IF a straight line be perpendicular **to each of two straight lines at their point of intersection, it** is also perpendicular to the plane in which they are. Let the straight line EF be perpendicular to... | |
| Euclides - Geometry - 1841 - 378 pages
...the planes AB, BC cannot but be a straight line. Wherefore, if two planes, &c. QED PROP. IV. THEOR. **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... | |
| John Playfair - Euclid's Elements - 1842 - 332 pages
...therefore common to the planes AB and BC, or it is the common section of these planes. PROP. IV. THEOR. **If a straight line stand at right angles to each of two straight lines** in the point of their intersection, it will also be at right angles to the plane in which these lines... | |
| Euclides - 1842 - 316 pages
...planes AB and BC, or it is the common section of these planes. Therefore, &c. QED PROP. IV. THEOR. **IF a straight line stand at right angles to each of two straight lines** in the point of their intersection: it will also be at right angles to the plane in which these lines... | |
| Euclides - 1845 - 546 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 :... | |
| Euclid - Geometry - 1845 - 218 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 shall * 4. 11. also be at right angles* to the plane passing... | |
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