 | Euclid, Dionysius Lardner - Euclid's Elements - 1828 - 542 pages
...If one angle of a triangle be right, the sum of the other two is equal to a right angle. (126) Coa. 2. — If one angle of a triangle be equal to the sum of the other two angles, that angle is a right angle. (127) COR. 3. — An obtuse angle of a triangle is greater... | |
 | Pierce Morton - Geometry - 1830 - 584 pages
...right-angled triangle, the right angle is equal to the sum of the other two angles : and, conversely, if ona angle of a triangle be equal to the sum of the other two, that angle shall be a right angle. Cor. 4. In a right-angled triangle, (he straight line, which... | |
 | Mathematics - 1835 - 684 pages
...right-angled triangle, the right angle is equal to the sum of the other two angles : and, conversely, if one angle of a triangle be equal to the sum of the other two, that angle / \ shall be a right angle. ~ Cor. 4. In a right-angled triangle, the straight line,... | |
 | John Charles Snowball - 1837 - 322 pages
...nearly. 12. If one angle of a triangle, plane or spherical, be equal to the sum of the other two angles, the greatest side is double of the distance of its middle point from the opposite angle. 13. Find the locus of the vertices of all right-angled spherical triangles which have the same hypothenuse... | |
 | Dionysius Lardner - Curves, Plane - 1840 - 386 pages
...(52.) If one angle of a triangle is right, the sum of the other two is equal to a right angle. (53.) If one angle of a triangle be equal to the sum of the other two angles, that angle is a right angle (54.) An obtuse angle of a triangle is greater, and an acute... | |
 | Euclides - 1842 - 316 pages
...angles CBA, BAC, ACB are equal to two right angles. Wherefore, if a side of a triangle, &c. QED COR. A. If one angle of a triangle be equal to the sum of the two others, it is a right angle : for the adjacent exterior angle is equal to the sum of the same two... | |
 | Euclides - 1845 - 546 pages
...perpendicular from the vertex, according as the angle is greater or less than a right angle. 11. If ofle angle of a triangle be equal to the sum of the other...distance of its middle point from the opposite angle. 12. If two exterior angles of a triangle be bisected, and from the point of intersection of the bisecting... | |
 | Great Britain. Council on Education - Education - 1848 - 596 pages
...Section 2. 1. Similar triangles are to pne another in the duplicate ratio of their 1mmologuous sides. 2. If one angle of a triangle be equal to the sum...distance of its middle point from the opposite angle. 3. If from the point of intersection of the straight lines which bisect two angles of an equilateral triangle... | |
 | J. Goodall, W. Hammond - 1848 - 390 pages
...Section 2. 1. Similar triangles are to one another in the duplicate ratio of their homologous sides. 2. If one angle of a triangle be equal to the sum...distance of its middle point from the opposite angle. 3. If from the point of intersection of the straight lines which beset two angles of an equilateral triangle... | |
 | Great Britain. Committee on Education - 1848 - 606 pages
...Section 2. 1. Similar triangles are to one another in the duplicate ratio of their homologuous sides. 2. If one angle of a triangle be equal to the sum of the other two, the gteatest side is double of the distance of its middle point from the opposite angle. 3. If from the... | |
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From this proposition, it is obvious that if one angle of a triangle be equal to the sum of the other two angles, that angle is a right angle, as is shewn in Euc. 
