| Robert Simson - Trigonometry - 1806 - 546 pages
...angle BAC to the third angle EDF. Therefore, if two triangles, &c. QED £ Book I. PROP. XXVII. THEOR. IF a straight line falling upon two other straight lines makes the alternate angles equal to one another, these two straight lines shall be parallel. Let the straight... | |
| William Nicholson - Natural history - 1809 - 684 pages
...parallel to C D. Therefore AB is parallel to C D. 16. Cor. If a straight line, falling upon two oilier straight lines, makes the exterior angle equal to the interior and opposite one on the same side of the line ; or makes the interior angles on the same side equal to two right... | |
| William Nicholson - 1809 - 716 pages
...BHG together ; and therefore (6) are equal together to the sum of two right angles. 15. Theorem V. If a straight line falling upon two other straight lines makes the alternate angles equal to one another, those two straight lines will be parallel. Let the straight... | |
| John Mason Good - 1813 - 714 pages
...line fall upon two parallel straight lines, it makes the alternate angles equal to one another; and the exterior angle equal to the interior and opposite upon the same side; and likewise the two interior angles upon the same side together equal to two right ansies. Prop. XXX.... | |
| Euclides - 1816 - 588 pages
...BAC to the third angle lEDF. Therefore, if two triangles, &c. QED Boo* I. ' „ PROP. XXVII. THEOR. IF a straight line falling upon two other straight lines makes the alternate angles equal to one another, these two straight lines shall be parallel. Let the straight... | |
| John Mason Good - 1819 - 800 pages
...be parallel. Prop. XX V 111. Theor. If a straight line falling upon two other straight lines make« the exterior angle equal to the interior and opposite...side of the line; or makes the interior angles upon i he same side together equal to two rirhc angles ; the two straight lines shall be parallefto one... | |
| John Playfair - 1819 - 354 pages
...line fall upon two parallel straight lines, it makes the alternate angles equal to one another ; and the exterior angle equal to the interior and opposite upon the same side ; and likewise the too interior angles upon the same side together equal to two right angles. Let the... | |
| William Nicholson - Natural history - 1821 - 402 pages
...and BUG together; and therefore (5) are equal together to the sum of two right angles. 15. Theorem V. If a straight line falling upon two other straight lines makes the alternate angles equal to one another, those two straight lines will be parallel. Let the straight... | |
| John Playfair - Circle-squaring - 1819 - 350 pages
...third angle BAC to the third angle EDF. Therefore, if two triangles, &c. Q.. ED PROP. XXVII. THEOR. If a straight line falling upon two other straight lines makes the alternate angles equal to one another, these too straight lines are parallel. Let the straight line... | |
| Euclid, Robert Simson - Geometry - 1821 - 514 pages
...line fall upon two parallel straight lines, it makes the alternate angles equal to one another; and the exterior angle equal to the interior and opposite upon the same side; and likewise the two interior angles upon the same side together equal to two right angles.* Let the... | |
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