 | Euclides - 1834 - 518 pages
...one and the same plane. Therefore, if three straight lines, &c. QED PROPOSITION VI. THEOR. — If iwo straight lines be at right angles to the same plane,...AB shall be parallel to CD. Let them meet the plane in the points B, D, and draw the straight line BD, to which drawt DE at right angles, in the f II.... | |
 | Robert Simson - Trigonometry - 1835 - 544 pages
...lines," &c. QED PROP. VI. THEOR. • Two straight lines, which are at right angles to the same plane, are parallel to one another. Let the straight lines AB, CD be at right angles to the same plane BDE; AB is parallel to CD. Let them meet the plane in the points B, D, and draw the straight line BD,... | |
 | Euclid - 1835 - 540 pages
...lines," &c. QED PROP. VI. THEOR. Two straight lines, which are at right angles to the same plane, are parallel to one another. Let the straight lines AB, CD be at right angles to the same plane BDE; AB is parallel to CD. Let them meet the plane in the points B, D, and draw the straight line BD,... | |
 | Mathematics - 1836 - 366 pages
...State Euclid's definition of proportion, and the algebraic definition, and shew that they coincide. 27. If two straight lines be at right angles to the same plane, shew that they are parallel to one another. What is Euclid's definition of parallel straight lines,... | |
 | A. Bell - Conic sections - 1837 - 180 pages
...and BE. Wherefore the three straight lines BC, BD, BE, are in one and the same plane. PROPOSITION VI. THEOREM. If two straight lines be at right angles...AB, CD, be at right angles to the same plane ; AB is parallel to CD. Let them meet the plane in the points B, D, and draw the straight line BD, to which... | |
 | A. Bell - Conic sections - 1837 - 180 pages
...lines BC, BD, BE, are in one and the same plane. PROPOSITION VI. THEOREM. If two straight lines he at right angles to the same plane, they shall be parallel...AB, CD, be at right angles to the same plane ; AB is parallel to CD. Let them meet the plane in the points B, D, and draw the straight line BD, to which... | |
 | John Playfair - Euclid's Elements - 1837 - 332 pages
...the same plane. PROP. VI. THEOR. Two straight lines which are at right angles to the same plane, are parallel to one another, Let the straight lines AB, CD be at right angles to the same plane BDE ; AB is parallel to CD. Let them meet the plane in the points B, D. Draw DE at right angles to... | |
 | Euclid, James Thomson - Geometry - 1837 - 410 pages
...wherefore BC, BD, BE are all in the same plane. Therefore, if three straight lines, &c. PROP. VI. THEOR. IF two straight lines be at right angles to the same plane, they are parallel to one another. Let the straight lines AB, CD be at right angles to the same plane BDE... | |
 | Robert Simson - Geometry - 1838 - 434 pages
...are in one ~""~~-Eand the same plane. Therefore, if three straight lines, &c. QED PROP. VI. THEOR. IF two straight lines be at right angles to the same...lines AB, CD be at right angles to the same plane ; AB is parallel to CD. Let them meet the plane in the points B, D, and draw the straight line B, D, to... | |
 | Euclides - Geometry - 1841 - 378 pages
...BD, BE are in one and the same plane. Therefore, if three straight lines, &c. Q ED PROP. VI. THEOR. If two straight lines be at right angles to the same...AB shall be parallel to CD. Let them meet the plane in the points B, D, and draw the straight * 11. 1. line BD, to which draw* DE at right angles, in the... | |
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If two straight lines be at right angles to the same plane, they shall be parallel to one another. Let the straight lines AB, CD be at right angles to the same plane : AB is parallel to CD. 
