 | Euclid - 1835 - 540 pages
...therefore AB is at right angles" to the plane HGK. For ^ b8.ll. the same reason, CD is likewise ^i ~v~ -r\ at right angles to the plane •*^ HGK. Therefore...each of them at right angles to the plane HGK. But two straight lines, which are at right angles to the same plane, are parallel0 to one another. Therefore... | |
 | John Playfair - Euclid's Elements - 1835 - 336 pages
...parallel to AB ; therefore AB is at right . H T> angles (7. 2. Sup.) to the plane •" "c •" HGK. For the same reason, CD is likewise at right angles to the plane HGK. Therefore AB, CD JJ ... are each of them at right angles / to the plane HGK. But if two / straight lines are at right... | |
 | John Playfair - Euclid's Elements - 1836 - 488 pages
...therefore AB is at right II -13 a 4. 2. Sup. b 7. 2. Sup. E•F angles b to the plane HGK. For the same A reason, CD is likewise at right angles to the plane...Therefore AB, CD are each of them at right angles to the Cplane HGK. But if &two straight lines are at right angles to the same plane, they are parallel0 to... | |
 | A. Bell - Conic sections - 1837 - 180 pages
...through them ; and EF is parallel to AB ; therefore AB is at right angles (I. 7) to the plane HGK. For the same reason, CD is likewise at right angles...right angles to the same plane, they are parallel (I. 6) to one another. Therefore AB is parallel to CD. PROPOSITION IX. THEOREM. If two straight lines... | |
 | John Playfair - Euclid's Elements - 1837 - 332 pages
...them : and EF is parallel to AB ; therefore AB is at right „ angles (7. 2. Sup.) to the plane A HGK. For the same reason, CD is likewise at right angles to the plane HGK. Therefore AB, CD jj \ -, are each of them at right angles ~* ' to the plane HGK. But if two straight lines are at right... | |
 | Euclid, James Thomson - Geometry - 1837 - 410 pages
...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 ; AB is parallel to CD. Let... | |
 | Robert Simson - Geometry - 1838 - 434 pages
...through them: and EF is parallel to AB, therefore AB is at right angles (8. 11.) to the plane HGK. For the same reason, CD is likewise at right angles...each of them at right angles to the plane HGK. But _, if two straight lines be at right angles K D to the same plane, they shall be parallel (6. 11.)... | |
 | Euclides - Geometry - 1841 - 378 pages
...through them: and EF is parallel to AB; therefore •3 11. AB is at right angles* to the plane HGK: for the same reason, CD is likewise at right angles...lines are at right angles to the same plane, they are * 6.11. parallel • to one another: therefore AB is parallel to CD. Wherefore, two straight lines,... | |
 | Euclides - 1842 - 316 pages
...^ To p and EF is parallel to AB; therefore AB [is at right angles (7. PI.) to the plane c к n HGK. For the same reason, CD is likewise at right angles...right angles to the same plane, they are parallel (6. PL) to one another: therefore AB is parallel to CD. Wherefore two straight lines, &c. QED PROP.... | |
 | John Playfair - Euclid's Elements - 1842 - 332 pages
...them : and EF is parallel to AB ; therefore AB is at right _ angles (7. 2. Sup.) to the plane HGK. For the same reason, CD is likewise at right angles...Therefore AB, CD are each of them at right angles D F to the plane HGK. But if two straight lines are at right angles C ^- jj to the same plane, they... | |
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For the same reason, CD is likewise at right angles to the plane HGK. Therefore AB, CD are each of them at right angles to the plane HGK. 
