| Euclides - 1855 - Страниц: 230
...above a plane. If two straight lines be at right angles to the same plane. If two straight lines be parallel. And one of them is at right angles to a plane. CONSEQUENCES. } Another part cannot be in it. ("Every plane which passes J. through it shall be at... | |
| 1857 - Страниц: 486
...if PA, QS meet in R, and PD, QC in S, prove that RS is parallel to AD. 15. If two straight lines be parallel, and one of them is at right angles to a plane ; the other also shall be at right angles to the same plane. 16. Find the angle at which a side of a pyramid is... | |
| 1858 - Страниц: 398
...through them, that is, to the plane in which they are. 11. PROP. VIII — If two straight lines be parallel, and one of them is at right angles to a plane, the other also shall be at right angles to the same plane. 12. PROP. XX. — If a solid angle be contained by... | |
| Great Britain. Parliament. House of Commons - 1858 - Страниц: 694
...through them, that is, to the plane in which they are. 11. PROP. VIII — If two straight lines be parallel, and one of them is at right angles to a plane, the other also shall be at right angles to the same plane. 12. PROP. XX. — If a solid angle be contained by... | |
| Joseph Charles Parkinson - 1860 - Страниц: 154
...through them, that is, to the plane in which they are. 11. PROP. VIII. — If two straight lines be parallel, and one of them is at right angles to a plane, the other also shall he at right angles to the same plane. 12. PROP. XX. — If a solid angle be contained by... | |
| Civil service - Страниц: 366
...passes through them, that is to the plane in which they are. PROP. VIII. — If two straight lines he parallel, and one of them is at right angles to a plane, the other also shall be at right angles, to the same plane. PROP. XX.— If a solid angle be contained by three... | |
| Eucleides - 1860 - Страниц: 396
...cut one another. If two straight lines be at right angles to the same plane. If two straight lines be parallel. And one of them is at right angles to a plane. CONSEQUENCES. } Another part cannot be in it. Every plane which passes through it shall be at right... | |
| Euclides - 1865 - Страниц: 402
...any point in the other, is in the same plane with the parallels. Prop. 8. If two straight lines be parallel, and one of them is at right angles to a plane; the other also shall be at right angles to the same plane. Prop. 9. Two straight lines which are each of them... | |
| Euclides - 1874 - Страниц: 342
...of ED and DA (XI. 4). But GH is parallel-to BC ; and if two straight lines be parallel, one of which is at right angles to a plane, the other is also at right angles to the plane (XI. 8) ; therefore 2. GH is at right angles to the plane of ED and DA ; and is perpendicular... | |
| Isaac Sharpless - 1879 - Страниц: 282
...parallel (I. 26) to AB. Proposition 7. Theorem.—If two straight lines be parallel, and one of them at right angles to a plane, the other is also at right angles to the same plane. Let AB and CD be two parallel straight lines, and let AB be at right angles to the plane EF; CD is... | |
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