 | Scottish school-book assoc - 1845 - 444 pages
...common section of the two planes is a straight line. GEOMETRY OF PLANES. PBOPOSITION LXXX — THEOREM. If a straight line stand at right angles to each of two traight lines in the point of their intersection, it will also e at right angles to the plane in which... | |
 | Euclid, John Playfair - Euclid's Elements - 1846 - 334 pages
...straight line BD is therefore common to the planes AB and BC, or it is the common sectioa of these planes. PROP. IV. THEOR. If a straight line stand at right...straight lines in the point of their intersection, it will also be at right angles to the plane in which these lines are. Let the straight line AB stand... | |
 | Dennis M'Curdy - Geometry - 1846 - 168 pages
...Th. If two planes cut one another, their common section is a straight line. Recite def. 7, 1. 4 Th. If a straight line stand at right angles to each of two straight lines, at their point of intersection, it will also be at right angles to the plane in which those straight... | |
 | Perry Fairfax Nursey - Industrial arts - 1846 - 536 pages
...too, by Euclid with an elegance fully equal to that by which any other author has proved it,) that "if a straight line stand at right angles to each of two stright lines at their point of intersection, it shall also be at right angles to every other line... | |
 | 1846 - 536 pages
...too, by Euclid with an elegance fully equal to that by which any other author has proved it,) that "if a straight line stand at right angles to each of two stright lines at their point of intersection, it shall also be at right angles to every other line... | |
 | John Playfair - Euclid's Elements - 1849 - 332 pages
...straight line BD is 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 hnes in the point of their intersection, it will also be at right angles to the plane in which these... | |
 | Euclides - 1855 - 230 pages
...If one part of a straight line is above a plane. If a straight line be at right angles to a plane. If a straight line stand at right angles to each of...straight lines, in the point of their intersection. If two straight lines cut one another. If two straight lines be drawn from a given point either in... | |
 | John Playfair - Euclid's Elements - 1855 - 340 pages
...straight line BD is therefore common to the planes AB and BC, or it is the common section of these olanes. PROP. IV. THEOR. If a straight line stand at right angles to each of two straight lines in the f nint of their intersection, it will also be at right angles to the plane in which these lines are.... | |
 | Euclides - 1855 - 270 pages
...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... | |
 | John Playfair - Geometry - 1855 - 334 pages
...therefore common to the planes AB and BC, or it is the common section of these nlanes. PROP. IV. THEOR. ^x If a straight line stand at right angles to each of two straight lmes in the point of their intersection, it will also be at right angles to the plane m which these... | |
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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 are. 
