 | John Playfair - Mathematics - 1806 - 320 pages
...therefore is in the same straight line with CB. Wherefore, if at a point, &c. QED PROP. XV. THEOR. IF two straight lines cut one another, the vertical, / or opposite, angles shall be equal. Let the two straight lines AB, CD cut one another in the point E ; the angle AEC shall... | |
 | Robert Simson - Trigonometry - 1806 - 546 pages
...therefore is in the same straight line with CB. Wherefore, if at a point, &c. QED PROP. XV. THEOR. IF two straight lines cut one another, the vertical, or opposite, angles shall be equal. Let the two straight lines AB, CD cut one another in the point E ; the angle AEC shall... | |
 | John Mason Good - 1813 - 714 pages
...right angles, these two straight lines •hall be in one and the same straight line. Piop. XV. Theor. If two straight lines cut one another, the vertical, or opposite, angles shall be equal. Prop. XVt Theor. If one side of a triangle be produced, the exterior angle is greater... | |
 | John Playfair - 1819 - 354 pages
...therefore is in the same straight line with CB. Wherefore, if at a point, &c. QED PROP. XV. THEOR. If two straight lines cut one another, the vertical, or opposite angles arc equal. Let the two straight lines AB, CD cut one another in the point E : the angle AEC shall be... | |
 | Peter Nicholson - Mathematics - 1825 - 1046 pages
...the same straight line with CB. Wherefore, if at э point, &c. Q. £. D. Proposition ХУ. Theorem. If two straight lines cut one another, the vertical, or opposite, angles shall be equal. . Let the two straight lines AB, CD, cut one another in the point £ ; the angle ABC... | |
 | Robert Simson - Trigonometry - 1827 - 546 pages
...therefore, is in the same straight line with CB. Wherefore, if at a point, &c. QED PROP. XV. THEOR. If two straight lines cut one another, the vertical, or opposite, angles shall be equal. Let the two straight lines AB, CD, cut one another in the point E : the angle AEC shall... | |
 | Pierce Morton - Geometry - 1830 - 584 pages
...one straight Une with another upon one side of it, are, together, equal to two right angles . . 5 (i) If two straight lines cut one another, the vertical or opposite angles are equal . . 5 (c) All the angles which are made upon one side of a straight line at the same point... | |
 | Mathematics - 1835 - 684 pages
...one straight line with another upon one side of it, are, together, equal to two right angles . 5 (*) If two straight lines cut one another, the vertical or opposite angles are equal . . 5 (c) All the angles which are made upon one side of a straight line at the same point... | |
 | Euclid - 1835 - 540 pages
...therefore is in the same straight line with.CB. Wherefore, " if at a point," &c. QED PROP. XV. THEOR. If two straight lines cut one another, the vertical, or opposite, angles shall be equal. Let the two straight lines AB, CD, cut one another in the point E; the angle AEC shall... | |
 | John Playfair - Geometry - 1836 - 148 pages
...remaining angle BED. In the same manner it can be shewn, that the angles AED, BEC are equal. Therefore, if two straight lines cut one another, the vertical or opposite angles shall be equal. Which was to be proved. COR. I. If two straight lines cut one another, the four angles"... | |
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IF two straight lines cut one another, the vertical, or opposite, angles shall be equal. 
