 | 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 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... | |
 | 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 - Circle-squaring - 1819 - 350 pages
...therefore is in the same straight line with CB. Wherefore, if at a point, &c. QED PROP. XV. THEOR. //" two straight lines cut one another, the -vertical, or opposite angles are equal. Let the two straight lines AB, CD cut one another in the point E ; " the angle AEC shall be equal to... | |
 | 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... | |
 | John Playfair - Euclid's Elements - 1832 - 358 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 are equal. Let the two straight lines AB, CD cut one another in the point E; the angle AEC shall be equal to the... | |
 | Mathematics - 1835 - 684 pages
...right angles, Cor. 2. Any angle of a triangle is less than two right angles. PKOP. 3. (Eue. i. 15.) If two straight lines cut one another, the vertical or opposite angles shall be equal. Let the two straight . lines AB, CD, cut J* one another in the к/ point E : the vertical... | |
 | 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... | |
| |
IF two straight lines cut one another, the vertical, or opposite, angles shall be equal. 
