| 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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