 | Elias Loomis - Conic sections - 1877 - 458 pages
...is their common section. Hence, if two planes, etc. 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... | |
 | J. B. Millar - Geometry, Descriptive - 1878 - 264 pages
...planes out one another, their common section is a straight line 2 Theorem III. If a straight line be perpendicular to each of two straight lines at their point of intersection, it shall also be perpendicular to their plane 3 Theorem IV. Every plane which contains the normal to another... | |
 | Isaac Sharpless - Geometry - 1879 - 282 pages
...is therefore their common section. Proposition 4. Theorem.—If a straight line be at right angles to each of two straight lines at their point of intersection, it is at right angles to the plane in which these straight lines are. Let AB be at right angles to each of... | |
 | Cornell University - 1880 - 868 pages
...symmetrical triedral angles, a segment of a sphere, the axis of a parabola. 2. If a straight line be perpendicular to each of two straight lines at their...intersection, it is perpendicular to the plane of those lines. 3. Two prisms are equal, if three faces including a triedral angle of one be respectively... | |
 | Oxford univ, local exams - 1880 - 396 pages
...sum of the rectangles contained by its opposite sides. 12. If a straight line stand at right angles to each of two straight lines at their point of intersection, it shall also be at right angles to the plane which passes through them, that is, to the plane in which... | |
 | Education, Higher - 1882 - 498 pages
...point of division is the centre of the inscribed circle. 16. If a straight line stand at right angles to each of two straight lines at their point of intersection, it shall also be at right angles to the plane which passes through them, that is, to the plane in which... | |
 | William Chauvenet - Geometry - 1884 - 384 pages
...perpendicular. PROPOSITION V.— THEOREM. 13. If a straight line is perpendicular to each of two strair/ht lines at their point of intersection, it is perpendicular to the plane of those lines. Let AP be perpendicular to PB and PC, at their intersection P; then, AP is perpendicular... | |
 | Charles Davies, Adrien Marie Legendre - Geometry - 1885 - 538 pages
...straight line ; which was to be proved. PROPOSITION IV. THEOREM. // a straight line is perpendicular to two straight lines at their point of intersection, it is perpendicular to the plane of those lines. BOOK VI. pendicular to every straight line of the plane which passes through P, and consequently,... | |
 | William Chauvenet, William Elwood Byerly - Geometry - 1887 - 332 pages
...At a given point in a plane one perpendicular can be erected to the plane, and but one. PROPOSITION IV. If a straight line is perpendicular to each of...intersection, it is perpendicular to the plane of those lines. Corollary I. At a given point of a straight line, one plane can be drawn perpendicular... | |
 | William Chauvenet, William Elwood Byerly - Geometry - 1887 - 331 pages
...At a given point in a plane one perpendicular can be erected to the plane, and but one. PROPOSITION IV. If a straight line is perpendicular to each of...intersection, it is perpendicular to the plane of those lines. Corollary I. At a given point of a straight line, one plane can be drawn perpendicular... | |
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If a straight line is perpendicular to each of two straight lines at their point of intersection, it is perpendicular to the plane of those lines. 
