If a straight line is perpendicular to each of two other straight lines at their point of intersection, it is perpendicular to the plane of the two lines. The Teaching of Geometry - Page 295by David Eugene Smith - 1911 - 339 pagesFull view - About this book
| Pierce Morton - Geometry - 1830 - 272 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
...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 R. PERKINS - 1856
...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 ; then... | |
| George Roberts Perkins - Geometry - 1860 - 443 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 ; then... | |
| Horatio Nelson Robinson - Geometry - 1860 - 453 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... | |
| Benjamin Greenleaf - Geometry - 1862 - 490 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... | |
| CHARLES DAVIES, LL.D. - 1863
...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 - 320 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 - 320 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... | |
| William Chauvenet - Geometry - 1871 - 368 pages
...PROPOSITION V.— THEOREM. / / • • '"( ' ' 13. 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. Let AP be perpendicular to PB and PC, at their intersection P; then, AP is perpendicular... | |
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