If, at a point in a straight line, two other straight lines, upon the opposite sides of it, make the adjacent angles together equal to two right angles, these two straight lines shall be in one and the same straight line. An Elementary Geometry and Trigonometry - Page 5by William Frothingham Bradbury - 1873 - 238 pagesFull view - About this book
| Moffatt and Paige - 1881 - 176 pages
...trapezvum. What is the hypothesis, and what is the conclusion in the enunciation of the 5th proposition 1 2. If at a point in a straight line, two other straight lines, upon the opposite sides of it, make the adjacent angles together equal to two right angles ; then these... | |
| Euclides - Euclid's Elements - 1881 - 236 pages
...Therefore BD is in the same straight line with CB. Wherefore, iŁ at a point, &c. QED Corollary.— IS at a point In a straight line, two other straight lines upon the iams aide of it, make each a right angle with it, these two straight lines shall coincide with... | |
| Education, Higher - 1882 - 498 pages
...and the angles contained by those sides also equal, the two triangles are equal in every respect. 4. If at a point in a straight line two other straight lines upon the opposite sides of it make the adjacent angles together equal to two right angles, these two straight... | |
| College of preceptors - 1882 - 528 pages
...lines, parallelogram, angle in segment of a circle, rectilinear figure described about a circle. 2. If at a point in a straight line two other straight lines on the opposite sides of it m;ike the adjacent angles together equal to two right angles, these two... | |
| Isaac Sharpless - Geometry - 1882 - 286 pages
...+ABE=R+ABE, and ABD = EBD ~ABE=R- ABE. .-. (Ax. 2) ABC+ABD = 2R. 5 BD E Proposition 16. Theorem. — If at a point in a straight line, two other straight lines on opposite sides of it, make the adjacent angles equal to two right angles, these two lines are in... | |
| Marianne Nops - 1882 - 278 pages
...DBA, ABC = Z. s CBE, EBD = two rt. L s. Wherefore the angles, &c. — QED PROPOSITION XIV., THEOREM 7. If at a point in a straight line two other straight lines, on the opposite sides of it, make the adjacent angles together equal to two right angles, these two... | |
| Joseph Hughes - Education - 1883 - 578 pages
...hypothesis BD = DC, and AB = AC. .'. By prop. 4 the triangles ABD, ACD are equal in every respect. QED 3. If at a point in a straight line, two other straight lines, upon the opposite sides of it, make the adjacent angles together equal to two right angles ; then these... | |
| Euclides - 1883 - 176 pages
...the angles made by these lines taken consecutively, amount to four -:-'ht angles. PROP. 14. THEOR. If, at a point in a straight line, two other straight lines, on the opposite sides of it, make the adjacent angles together equal to two right angles, the two straight... | |
| Stewart W. and co - 1884 - 272 pages
...CBE, EBD, are two right angles ; therefore DBA, ABC, are together equal to two right angles. XIV. — If, at a point in a straight line, two other straight lines, upon the opposite sides of it, make the adjacent angles together equal to two right angles, these two straight... | |
| Euclides - 1884 - 182 pages
...angles thus formed cannot be both acute, nor can they be both obtuse. 49. PROPOSITION XIV. — THEOREM. If at a point in a straight line two other straight lines upon the opposite sides of it make the adjacent angles together equal to two right angles, these two straight... | |
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