| Euclides - Euclid's Elements - 1837 - 112 pages
...3. that Zs DBA + ABC = the two rt. Zs CBE + EBD. PROPOSITION XIV. (Argument ad absurdum). Theorem. If, at a point in a straight line, two other straight lines on opposite sides of it make the adjacent angles together equal to two right angles, these two straight... | |
| Euclid - Geometry - 1838 - 470 pages
...are together equal to two right angles. Wherefore, when a straight line, &c. Q,. ED PROP. XIV. THEOR. IF, at a point in a straight line, two other straight...opposite sides of it, make the adjacent angles together etlual to two right angles, these two straight lines shall be in one and the same straight line. n... | |
| Euclides - Geometry - 1841 - 378 pages
...therefore DBA, ABC are together equal to two right angles. Wherefore, the angles, &c. QED PROP. XIV. THEOR. If, at a point in a straight line, two other straight...lines shall be in one and the same straight line. At the point B in the straight line AB, let the two straight lines ( A BC, BD upon the opposite sides... | |
| John Playfair - Euclid's Elements - 1842 - 332 pages
...angles ; because their sum is equal to that of the two adjacent angles DBA, ABC. PROP. XIV. THEOR. If, at a point in a straight line, two other straight...equal to two right angles, these two straight lines are in one and the same straight line. At the point B in the straight line AB, let the two straight... | |
| Euclid - Geometry - 1845 - 218 pages
...together equal to two right angles. Wherefore, when a straight line, &c. QED PROPOSITION XIV. THEOR. — If, at a point in a straight line, two other straight...lines shall be in one and the same straight line. At the point B in the straight line AB, let the two straight lines BC, BD upon the opposite sides of... | |
| Euclides - 1845 - 546 pages
...to two right angles, (ax. 1.) Wherefore when a straight line, &c. QE ». PROPOSITION XIV. THEOREM. If at a point in a straight line, two other straight...lines shall be in one and the same straight line. At the point B in the straight line AB, let the two straight lines BC, BD upon the opposite sides of... | |
| Euclid, James Thomson - Geometry - 1845 - 382 pages
...it but BD, which therefore is in the same straight line with CB. Wherefore, if at a point, &c. Cor. If, at a point in a straight line, two other straight lines meet on the opposite sides of it, and make equal angles with the parts of it on opposite sides of the... | |
| Euclides - 1846 - 292 pages
...to two right angles. Wherefore, The angles, which one straight line %c. <t. i:.j>. PROP. XIV. THEOR. If, at a point in a straight line, two other straight...lines shall be in one and the same straight line. At the point B in the straight line AB, let the two straight lines BC, BD, upon the opposite sides... | |
| Great Britain. Admiralty - Geometry - 1846 - 128 pages
.../_», .'. Z DBA + L ABC = 2 rt. L s. Ax ' '• Therefore the angles, &c. PROP. XIII. THEOR. 14. 1 Eu. If at a point in a straight line, two other straight...lines shall be in one and the same straight line. At the point B in AB let BC, BD, on the oppo. sides of AB, make the adj. /_ s ABC + Z.ABD= 2 rt. /_s;... | |
| Great Britain. Admiralty - Geometry - 1846 - 128 pages
...rt. /.s, .-. /. DBA + L ABC = 2 rt. L s. Ax K Therefore the angles, &c. PROP. XIII. THEOR. 14. 1 Eu. If at a point in a straight line, two other straight...lines shall be in one and the same straight line. At the point B in AB let BC, BD, on the oppo. sides of AB, make the adj. /. s ABC + /.ABD= 2 rt. /.s;... | |
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