 | George Albert Wentworth - 1884 - 264 pages
...equal. 31. Corollary II. The sum of the acute angles of a right triangle is equal to 90°. 32. Theorem. An exterior angle of a triangle is equal to the sum of the two opposite interior angles. 33. Theorem. The sum of the angles of a quadrilateral is equal to 360°. 34. Theorem. The sum of the... | |
 | Samuel Edward Warren - Geometrical drawing - 1887 - 200 pages
...Fig. 52, are exterior angles. The last theorem now naturally leads to the following : — Theorem. — An exterior angle of a triangle is equal to the sum of the two opposite interior angles. The angles d and CAB, Fig. 53, arc together equal to two right angles, being adjacent angles, or all... | |
 | George Albert Wentworth - 1889 - 276 pages
...Corollary II. The sum of the acute angles of a right triangle is equal to 90°. y i /" / 32. Theorem. An exterior angle of a triangle is equal to the sum of the two opposite interior angles. X 33. Theorem. The sum of the angles of a quadrilateral is equal to 360°. 34. Theorem. The sum of... | |
 | George Albert Wentworth - 1889 - 264 pages
...31. Corollary II. The sum of the acute angles of a right triangle is equal to 90°. ~ , 32. Theorem. An exterior angle of a triangle is equal to the sum of the two opposite interior angles. 33. Theorem. The sum of the angles of a quadrilateral 'is equal to 360°. 34. Theorem. The sum of the... | |
 | Paul Carus - Philosophy - 1889 - 286 pages
...to the stock of our knowledge something new, -.vhich we have not known before. In proving that the exterior angle of a triangle is equal to the sum of the two opposite interior angles of the same, we amplify our knowledge of the triangle by mere ratiocination, a priori. Kant uses even... | |
 | James Wallace MacDonald - Geometry - 1889 - 80 pages
...angles are complements of each other. SCHOLIUM. The exterior angle formed by prolonging one of the sides of a triangle is equal to the sum of the two opposite interior angles. Proposition XXXIV. A Theorem. 71. In an isosceles triangle the angles opposite the equal sides are... | |
 | James Wallace MacDonald - Geometry - 1894 - 76 pages
...angles are complements of each other. SCHOLIUM. The exterior angle formed by prolonging one of the sides of a triangle is equal to the sum of the two opposite interior angles. Proposition XXXIV. A Theorem. 71. In an isosceles triangle the angles opposite the equal sides are... | |
 | Edward Albert Bowser - Geometry - 1890 - 418 pages
...= 2rt. Zs. (Ax. 1) QED 98. COR. 1. Since Z EBD = ZA, and Z CBE = ZC, .-.ZCBD = ZA + ZC. Hence, the exterior angle of a triangle is equal to the sum of the two opposite interior angles. 99. COR. 2. If two angles of a triangle are given, or merely their sum, the third angle can be found... | |
 | Seth Thayer Stewart - Geometry - 1891 - 428 pages
...supplementary angles is five times the other. What are the angles ? PROPOSITION X. 13§. Theorem : Any exterior angle of a triangle is equal to the sum of the two opposite interior angles. Statement : Let / 2 3 be a triangle, and let one of the sides, as 2 3, be extended, making the exterior... | |
 | Henry Martyn Taylor - 1893 - 486 pages
...6. Construct a right-angled triangle, having given one side and the angle opposite. PROPOSITION 32. An exterior angle of a triangle is equal to the sum of the two interior opposite angles; and the sum of the three interior angles of a triangle is equal to... | |
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An exterior angle of a triangle is equal to the sum of the two opposite interior angles. 
