 | William Shakespeare - Sonnets, English - 1890 - 356 pages
...be said, indeed, that tlie evidence altogether is not of equal cogency with the demonstration that the three angles of a triangle are together equal to two right angles. This may be freely granted, and if such a demonstration is required, the Sonnet-problem is no doubt... | |
 | William Kingdon Clifford - Mathematics - 1891 - 312 pages
...our second assumption about space leads very easily to a theorem of especial importance, viz. that the three angles of a triangle are together equal to two right angles. If we draw through A, a corner of the triangle ABC (fig. 20), a line DAE, making with the side A 0... | |
 | Electronic journals - 1891 - 790 pages
...figures it is the only one of which the form cannot be altered, if the sides remain constant, and that the three angles of a triangle are together equal to two right angles, so that if we know two of the angles of any triangle we can at once calculate the third angle by subtracting... | |
 | Euclid - Geometry - 1892 - 460 pages
...of an equilateral triangle is two'third* of a right angle. EXERCISES ON PROPOSITION 32 1. Prove that the three angles of a triangle are together equal to two right angles, (i) by drawing through the vertex a straight line parallel to the base ; (ii) by joining the vertex... | |
 | Alfred Fouillée - Education - 1892 - 380 pages
...is well to name the inventors of these beautiful theorems if opportunity offers. For instance, that the three angles of a triangle are together equal to two right angles, that the homologous sides of equiangular triangles are proportional, that angles in a semicircle are... | |
 | Madeline Agar - Gardens - 1911 - 316 pages
...line from D to A is at right angles to A B. This is a practical application of the proposition that the three angles of a triangle are together equal to two right angles. In the diagram the value of the angles has been marked, and it will be seen that the equilateral triangle... | |
 | William Ernst Paterson - Logarithms - 1911 - 262 pages
...standing on different arcs are in the same ratio as the lengths of the arcs. Triangles. Prop. 6. (a) The three angles of a triangle are together equal to two right angles. (b) If one side be produced the exterior angle equals the sum of the two interior opposite angles.... | |
 | Great Britain. Board of Education - Mathematics - 1912 - 632 pages
...only one question out of each of the pairs of alternatives should be answered. Either 4o. Prove that the three angles of a triangle are together equal to two right angles. and meets AC in D, is 2 inches in length. Draw the triangle with the help of your protractor, stating... | |
 | Great Britain. Board of Education - Education - 1912 - 1044 pages
...only one question out of each of tie }:<ii>-n of altenxithes should be answered. Either 4a. Prove that the three angles of a triangle are together equal to two right angles. ABC is a triangle in which AB = AC, and the angle A is known to be 40°. It is also known that the... | |
 | Newfoundland Council of Higher Education - 1913 - 228 pages
...equal to two right angles, then in each case the two straight lines are parallel. (10) 4. Prove that the three angles of a triangle are together equal to two right angles. ABCDEFG is a seven-sided figure. The angles A and B are each equal to the angle of a regular five-sided... | |
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... the three angles of a triangle are together equal to two right angles, although it is not known to all. 
