| Pierce Morton - Geometry - 1830 - 584 pages
...is a straight line. Therefore, &c. PROP. 3. (Eue. xi. 4.) 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 every other straight line which passes through the same point and lies... | |
| Mathematics - 1835 - 684 pages
...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 they are . .128 (¿) Any number of straight lines, which... | |
| George Roberts Perkins - Geometry - 1856 - 460 pages
...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 point of intersection P ;... | |
| Horatio Nelson Robinson - Geometry - 1860 - 470 pages
...implicitly assumed in the definitions of this Book. THEOREM III. If a straight line stand at right angles to each of two other straight lines at their point of intersection, it will be at right angles to the plane of those lines. Let AB stand at right angles to EFand CD, at their... | |
| George Roberts Perkins - Geometry - 1860 - 472 pages
...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 point of intersection P... | |
| Benjamin Greenleaf - Geometry - 1862 - 518 pages
...straight line. PROPOSITION IV. — THEOREM. 401. If a straight line is perpendicular to each of two straight lines, at their point of intersection, it is perpendicular to the plane in which the two lines lie. Let the straight line AB be perpendicular to each of the straight lines... | |
| Benjamin Greenleaf - Geometry - 1861 - 638 pages
...straight line. PROPOSITION IY. — THEOREM. 401. If a straight line is perpendicular to each of two straight lines, at their point of intersection, it is perpendicular to the plane in which the two lines lie. Let the straight line AB be perpendicular to each of the straight lines... | |
| Adrien Marie Legendre - Geometry - 1863 - 464 pages
...line ; which was to be proved. PROPOSITION IY. THEOREM. If a straight line is perpendicular to two straight lines at their point of intersection, it is perpendicular to the plane of those lines. AP be perpendicular to every line of the plane which pusses through P, and consequently,... | |
| Benjamin Greenleaf - Geometry - 1863 - 504 pages
...straight line. B 1> PROPOSITION IV. — THEOREM. 401. If a straight line is pcrpemlicular to each of two straight lines, at their point of intersection, it is perpendicular to the plane in which the two lines lie. Let the straight line AB be perpendicular to each of the straight lines... | |
| Benjamin Greenleaf - Geometry - 1868 - 340 pages
...straight line. PROPOSITION IV. — THEOREM. 401. If a straight line is perpendicular to each of two straight lines, at their point of intersection, it is perpendicular to the plane in which the two lines lie. Let the straight line AB be perpendicular to each of the straight lines... | |
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