 | Euclid - Geometry - 1892 - 460 pages
...perpendicular to one another when the dihedral angle formed by them is a right angle. PROPOSITION 19. THEOREM. If two intersecting planes are each perpendicular to a third plane, their common section shall also be perpendicular • ' to that plane. Let each of the planes AB, BC be perp.... | |
 | William Chauvenet - 1893 - 340 pages
...from any point of one plane perpendicular to the other will lie in the first plane. PROPOSITION XVI. If two intersecting planes are each perpendicular to a third plane, their intersection is also perpendicular to that plane. PROPOSITION XVII. Through any given straight line a plane can be... | |
 | George Clinton Shutts - Geometry - 1894 - 412 pages
...in plane CD _L to BD and follow plan of proof in Cor. I. PROPOSITION ХХУП. 455. Theorem. // two planes are each perpendicular to a third plane, their intersection is perpendicular to that plane. c M Let С D and EF be two planes, each perpendicular to the plane MN, and let A 0 be the line of intersection... | |
 | Charles Ambrose Van Velzer, George Clinton Shutts - Geometry - 1894 - 522 pages
...the other. . See S«f . 1 of Cor. I, and Art MS. PROPOSITION XXVI. THHORBM. 380. If two planes are perpendicular to a third plane, their intersection is perpendicular to that plane. Let CD and E f be two planes, each perpendicular to tlie plane MN, and let AO be the line of intersection... | |
 | John Macnie - Geometry - 1895 - 386 pages
...equidistant from HH' and KK', plane DB bisects the dihedral angle HGG'K'. PROPOSITION XX. THEOREM. 475. If two intersecting planes are each perpendicular to a third, plane, their intersection is also perpendicular to the third plane. Given: AB, the intersection of two planes, PQ, RS, each perpendicular... | |
 | George Albert Wentworth - Mathematics - 1896 - 68 pages
...A plane perpendicular to the edge of a dihedrdl «ngle is perpendicular to each of its faces. 520. If two intersecting planes are each perpendicular to a third plane, their intersection is also perpendicular to that plane. 521. Cor. 1. If a plane is perpendicular to each of two intersecting... | |
 | Andrew Wheeler Phillips, Irving Fisher - Geometry - 1896 - 570 pages
...perpendicular to QS. Prove BA and BA' coincide. PROPOSITION XIX. THEOREM 5*78. If two intersecting planes are perpendicular to a third plane, their intersection is perpendicular to that plane. GIVEN — the planes MC and EB perpendicular to the plane PQ and intersecting in AB. To PROVE AB perpendicular... | |
 | Joseph Johnston Hardy - Geometry, Analytic - 1897 - 398 pages
...perpendicular to a plane, every plane passed through the line is perpendicular to the first plane. 44. If two intersecting planes are each perpendicular to a third plane, their intersection is also perpendicular to that plane. 45. Through a given straight line not perpendicular to a plane, one... | |
 | George Washington Hull - Geometry - 1897 - 408 pages
...the same point, which is impossible. Hence AB lies in PQ. § 375 PROPOSITION XXII. THEOREM. 415. // two intersecting planes are each perpendicular to a third plane, their intersection is also perpendicular to that plane. Given—The planes PQ and RS, intersecting in the line AB, perpendicular... | |
 | Andrew Wheeler Phillips, Irving Fisher - Geometry - 1896 - 574 pages
...perpendicular to QS. Prove BA and BA' coincide. PROPOSITION XIX. THEOREM 578. If two intersecting planes are perpendicular to a third plane, their intersection is perpendicular to that plane. GIVEN — the planes MC and EB perpendicular to the plane PQ and intersecting in AB. To PROVE AB perpendicular... | |
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If two intersecting planes are each perpendicular to a third plane, their intersection is perpendicular to that plane. 
