| 1827
...or, in other words, either of the acute angles is the complement of the other. And, conversely, if **one angle of a triangle be equal to the sum of the** other two, that angle is a right angle. For it is half the sum of the three angles, ie half of two... | |
| Euclid, Dionysius Lardner - Euclid's Elements - 1828 - 324 pages
...angle of a triangle be right, the sum of the other two is equal to a right angle. (126) COR. 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 - 1830
...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. " For, if the right angle be divided into parts equal... | |
| Dionysius Lardner - Geometry - 1838 - 332 pages
...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... | |
| Euclides - History - 1842
...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... | |
| Great Britain. Council on Education - Education - 1848
...the opposite angle. (The first case only of this proposition need be demonstrated.) Section 2. 2. If **one angle of a triangle be equal to the sum of the** other two, the greatest side is double of the distance of its middle point from the opposite angle.... | |
| J. Goodall, W. Hammond - 1848
...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 of the** other two, the greatest side is double of the distance of its middle point from the opposite angle.... | |
| Euclides - 1850
...having the angle A double the angle C; shew that the side BC is less than double the side AB. 36. If **one angle of a triangle be equal to the sum of the** other two, the greatest side is double of the distance of its middle point from the opposite angle.... | |
| Charles Astor Bristed - 1852
...number 95 be denoted by 137 ? S. Prove that and also that — 9. Assuming the formula cos A = -- rr -- , **find an expression for the area of a plane triangle in terms of** the sides. Simplify the expression in the case of an equilateral triangle. s. Find the equation of... | |
| Popular educator - 1854
...angle of a triangle be a right angle, the sum of the other two i» a right angle. Corollary 5.—If **one angle of a triangle be equal to the sum of the** other two, it is a right angle. Corollary 6.—If one angle of a triangle be greater than the sum of... | |
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