 | Wooster Woodruff Beman, David Eugene Smith - Geometry - 1895 - 344 pages
...perpendicular to a plane, through a given point, by the use of two carpenter's squares. 216 Theorem 9. If one of two parallel lines is perpendicular to a plane the other is also. Given OY II OT, OY _L plane MN at 0, and O'Y' meeting plane MN at 0'. To prove that O'Y' _L... | |
 | George Albert Wentworth - Mathematics - 1896 - 68 pages
...its middle point. 483. Two straight lines perpendicular to the same plane are parallel. 484. Cor. 1. If one of two parallel lines is perpendicular to a plane, the other is also perpendicular to the plane. 485. Cor. 2. If two straight lines are parallel to a third straight... | |
 | George Washington Hull - Geometry - 1897 - 408 pages
...COR.— The line BC is perpendicular to the plane of the triangle APD. PROPOSITION XI. THEOREM. 386. If one of two parallel lines is perpendicular to a plane, the other is also perpendicular to the plane. Given—AB and CD parallel, and AB perpendicular to MN. To Prove—CD... | |
 | Joseph Johnston Hardy - Geometry, Analytic - 1897 - 398 pages
...from the point to the plane. 35. Two straight lines perpendicular to the same plane are parallel. 36. If one of two parallel lines is perpendicular to a plane, the other is also perpendicular to the plane. 37. If two straight lines are parallel to a third straight line... | |
 | Wooster Woodruff Beman, David Eugene Smith - Geometry - 1899 - 416 pages
...outside of a plane, not more than one line can be drawn perpendicular to that plane. PROPOSITION IX. 342. Theorem. If one of two parallel lines is perpendicular to a plane, the other is also. M I Given 0 Y II 0' Y', 0 Y -L plane MN at O, and 0' Y' meeting plane MN at 0'. To prove that... | |
 | George Albert Wentworth - Geometry, Solid - 1899 - 246 pages
...are both _L to BD. Therefore, AB and CD are parallel. §508 § 492 § 501 § 104 0. ED 520. COR. 1. If one of two parallel lines is perpendicular to a plane, the other is also perpendicular to the plane. For if through any point O of CD a line is drawn _L to MN, it is... | |
 | Webster Wells - Geometry - 1899 - 424 pages
...drawn in the plane through its foot.] (§ 398) .-. AB II CD. SOLID GEOMETRY. — BOOK VI. 419. Cor. I. If one of two parallel lines is perpendicular to a plane, the other is also perpendicular to the plane. Given lines AB and CD II, and A c AB _L to plane MN. To Prove CD... | |
 | Harvard University - Geometry - 1899 - 39 pages
...parallel and lying in the same direction, they are equal and their planes are parallel. THEOREM VIII. If one of two parallel lines is perpendicular to a plane, the other is also perpendicular to that plane. 17 THEOREM IX. All plane angles of the same diedral angle are... | |
 | Wooster Woodruff Beman, David Eugene Smith - 1903 - 158 pages
...and AX ± OX, § 339 II ^X, and similarly for all other _k. I, prop. XVI, cor. 3 PROPOSITION IX. 342. Theorem. If one of two parallel lines is perpendicular to a plane, the other is also. Given OY II O' Y', OY J- plane MN at O, and O' Y' meeting plane MN at O'. To prove that O'Y'±MN.... | |
 | Wooster Woodruff Beman, David Eugene Smith - Geometry, Solid - 1900 - 160 pages
...AX, and similarly for all other -k Why? § 330, 2 § 339 I, prop. XVI, cor. 3 PROPOSITION IX. 342. Theorem. If one of two parallel lines is perpendicular to a plane, the other is also. Given 0 Y II 0' Y', 0 Y J- plane MN at 0, and 0' Y' meeting plane MN at 0'. To prove that... | |
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THEOREM. If one of two parallel lines is perpendicular to a plane, the other will also be perpendicular to this plane. Let AP & ED be parallel lines, of which AP is perpendicular to the plane MN ; then will ED be also perpendicular to this plane. 
