| Euclid - Geometry - 1892 - 518 pages
...perp. to this plane. QED PROPOSITION 4. THEOREM. [Euclid's Proof.] If a straight line is perpendicular **to each of two straight lines at their point of intersection, it** shall also be perpendicular to the plane in which they lie. Let the st. line EF be perp. to each of... | |
| Yale University - 1892 - 139 pages
...area will be a maximum when these sides are at right angles. 7. 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. 8. Define symmetrical polyhedral angles. Illustrate the... | |
| Arthur Latham Baker - Geometry, Solid - 1893 - 148 pages
...straight line and a point without, § 5. PROPOSITION II. THEOREM. 15. 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. Notation. Let m and n be two straight lines which determine... | |
| William Chauvenet - 1893 - 340 pages
...from the foot of the perpendicular. PROPOSITION IV.—THEOREM. 10. 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... | |
| Examinations - 1893
...plane, surface vf revolution, oblique prism, sphere. 15 2 Prove that if a straight line is perpendicular **to each of two straight lines at their point of intersection, it** is perpendicular to the plane of the two lines. 1 8 3 Prove that the sum of the face angles of any... | |
| Andrew Wheeler Phillips, Irving Fisher - Geometry - 1897 - 376 pages
...plane is perpendicular to the line. PROPOSITION III. THEOREM 511. If a straight line is perpendicular **to each of two straight lines at their point of intersection, it** is perpendicular to Hie plane of those lines. GIVEN — the straight line BG perpendicular to each... | |
| Andrew Wheeler Phillips, Irving Fisher - Geometry - 1897 - 374 pages
...plane is perpendicular to the line. PROPOSITION III. THEOREM 511. 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. GIVEN—the Straight line BG perpendicular to each of... | |
| Mathematics - 1898 - 208 pages
...prism, a parallelopiped, a pyramid, a cone, a cylinder, a sphere. 2. 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. 3. If a pyramid is cut by a plane parallel to its base,... | |
| Yale University - 1898 - 212 pages
...prism, a parallelepiped, a pyramid, a cone, a cylinder, a sphere. 2. 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. 3. If a pyramid is cut by a plane parallel to its base,... | |
| James Howard Gore - Geometry - 1898 - 232 pages
...from the foot of the perpendicular. PROPOSITION III. THEOREM. 337. 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. To prove that BA is perpendicular to EA and hence perpendicular... | |
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