 | Edward Albert Bowser - Geometry - 1890 - 414 pages
...in the same plane, and they are both J_ to BD. .-. ABis II to CD. (487) zn? (70) QED N| 510. COR. 1. If one of two parallel lines is perpendicular to a plane, the other is alno perpendicular to that plane. A c For, if AB is || to CD, and J_ to the plane MN, then a J_ to... | |
 | William Chauvenet - 1893 - 340 pages
...parallel and lying in the same direction, they are equal and their planes are parallel. PROPOSITION XI. If one of two parallel lines is perpendicular to a plane, the other is also perpendicular to that plane. Corollary. Two straight lines perpendicular to the same plane are parallel... | |
 | William C. Bartol - Geometry, Solid - 1893 - 112 pages
...which has been passed through A, parallel to PQ; ie, MN is parallel toPQ. PROPOSITION VII. 23. THEOREM. If one of two parallel lines is perpendicular to a plane, the other is also perpendicular to the plane. E D Let the line BA be perpendicular to the plane xy; and let the line... | |
 | 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 MN. Proof. 1.... | |
 | Wooster Woodruff Beman, David Eugene Smith - Geometry - 1895 - 346 pages
...OC2 + OA2 - 2 . PO2 + 2 . OB2 + 2 - BC2 ; .'. PB2 = PO- + OB-> ; .'. /_ POB is a rt. ^/. Theorem 9. 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 0, and O'Y' meeting plane MN at 0'. To prove that O'Y' J_ MN. Proof.... | |
 | 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 line,... | |
 | 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 perpendicular... | |
 | 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 they are... | |
 | 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 ± MN.... | |
 | 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 equal. THEOREM... | |
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If one of two parallel lines is perpendicular to a plane, the other is also perpendicular to the plane. 
