| Alexander Mackay - 1850 - 394 pages
...they confined themselves to the teaching of such simple truths as that two and two make four, and that **the three angles of a triangle are together equal to two right angles** ? And what holds good of a branch of secular education, holds good of it in its entirety. If mathematics... | |
| J. D. Bell - 1850 - 488 pages
...there are principles of numbers and of geometry, which will exist forever. Such is the truth, that **the three angles of a triangle are together equal to two right angles.** Such is the truth, that the square described on the hypothenuse of a right-angled triangle, is equal... | |
| Samuel Bailey - 1851 - 254 pages
...An exterior angle of a triangle is equal to both its opposite interior angles, and all the interior **angles of a triangle are together equal to two right angles. The** exterior angle BCD formed by the production of the side AC of the triangle ABC, is equal to the / \... | |
| Edward Miall - 1853 - 464 pages
...which make their appeal to the intellect, without having within us a spark of spiritual life. That **the three angles of a triangle are together equal to two right angles** may be a truth in which the derived mind may meet the Uncreated Mind, without any conscious commingling... | |
| 1853 - 530 pages
...advanced as far as the thirty-second proposition of the first book of Euclid. He had perceived that **the three angles of a triangle are together equal to two right** ones, and was searching for a satisfactory proof, when his father surprised him in his forbidden speculations.... | |
| Laurens Perseus Hickok - 1854 - 726 pages
...originate phenomena. 3. Space and time have a necessity of being independently of all phenomena. — That **the three angles of a ', -<* triangle are together equal to two right angles** is a necessary and universal truth, but yet not independent. Provided the triangle be, then this truth... | |
| William Somerville Orr - 1854 - 534 pages
...from the formula — sin. A sin. B ein. C abc without reference to Euclid's demonstration. Thus, since **the three angles of a triangle are together equal to two right angles,** we have A + В + С = 180°. .-. sin. (А + В) = sn. (180° — С) = sin. C. Л sin. A cos. B + sin.... | |
| William Pease - 1856 - 108 pages
...cannot be formed. This rule of comparison does not extend to the angles of a triangle ; for, since **the three angles of a triangle are together equal to two right angles,** or 180°; in a right-angled triangle, one angle (the right angle) is equal to the sum of the other... | |
| 1857 - 1266 pages
...given equiangular and equilateral hexagon. SECTION IV. — Show how to prove experimentally : 1. That **the three angles of a triangle are together equal to two right angles.** 2. That the square of the hypothenuse of a right angled triangle is equal to the sum of the squares... | |
| 1857 - 400 pages
...the Line of Direction to any point in the Base Line will be together equal to a right angle ; tecause **the three angles of a triangle are together equal to two right angles.** Hence the side at 30° to the perspective centre will make with •the Base Line an angle of 60°.... | |
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