 | Stephen Thomas Hawtrey - 1878 - 202 pages
...that which has been made known to us ? Euclid. I have. Strong. May I ask what is it ? Euc. It is that if two angles of a triangle are equal, the sides opposite to those angles are also equal. Strang. And, revered philosopher, can you give a proof that this is true,... | |
 | Walter Percy Workman - 1880 - 248 pages
...angles ABC, ACB are equal. And it was shown in the former proposition that if the two angles at the base of a triangle are equal, the sides opposite to them are equal. [i. 6. Hence AB is equal to AC. QED 3. An obvious modification of Euc. i. 24. Let EDF be any triangle.... | |
 | College of preceptors - 1882 - 528 pages
...Explain how you would find out practically, by folding the paper, whether BAD is a right angle or not. 2. If two angles of a triangle are equal, the sides opposite to them are equal. 3. If one side of a triangle is produced, the exterior angle shall be greater than either of the interior... | |
 | Franklin Ibach - Geometry - 1882 - 208 pages
...isosceles triangle bisects the base at right angles. ELEMENTS OF PLANE GEOMETRY. THEOREM XXXII. 98. CONVERSELY. — If two angles of a triangle are equal, the sides opposite them are equal, and the triangle is isosceles. С In the A ABC, let Z. a = ¿- b. To prove that A С... | |
 | Mathematical association - 1883 - 86 pages
...or directly by Superposition.] COR. If a triangle is equilateral, it is also equiangular. THEOR. 8. If two angles of a triangle are equal, the sides opposite to those angles are equal. [By Theor. 6 or directly by Superposition.] COR. If a triangle is equiangular,... | |
 | Edward Olney - Geometry - 1883 - 352 pages
...223. COROLLARY 3. — In an isosceles triangle the angles opposite the equal sides are equal ; and, conversely, if two angles of a triangle are equal, the sides opposite are equal, and the triangle is isosceles. Thus, if AB = BC, arc a = arc e ; and hence, angle A, measured... | |
 | Mathematical association - 1884 - 146 pages
...the triangles into which the bisector of the vertical angle divides the isosceles triangle. THEOR. 8. If two angles of a triangle are equal, the sides opposite to those angles are equal. Let ABC be a triangle having the angle ABC equal to the angle ACB : A A< c1... | |
 | Charles Davies, Adrien Marie Legendre - Geometry - 1885 - 538 pages
...base, bisects the angle at the vertex, and is perpendicular to the base. PROPOSITION XII. THEOREM. // two angles of a triangle are equal, the sides opposite to them are also equal, and consequently, the triangle is isosceles. In the triangle ABC, let the angle ABC be... | |
 | 1886 - 610 pages
...AB" is " sq. on AB" and for "the rectangle contained by the straight lines AB, CD"is"rect.AB, CD." 1. If two angles of a triangle are equal, the sides opposite to those angles shall be equal. 2. D is a point within the triangle ABC. Prove that BD, DC are less than... | |
 | William Chauvenet, William Elwood Byerly - Geometry - 1887 - 331 pages
...AB'; are equal to each other, by Proposition IX., and B is equal to B ' . PROPOSITION XL-THEOREM. 27. If two angles of a triangle are equal, the sides opposite to them are equal, and the triangle is isosceles. Let the angles BAC and SCA of the triangle ABC be ©qual, then are the sides AB and BC... | |
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Conversely: if two angles of a triangle are equal, the sides opposite to them are equal, and the triangle it itosceles. 
