| American School (Chicago, Ill.) - Engineering - 1903
...triangle are known, the third can be formed by subtracting their sum from two right angles. Corollary VI. **An exterior angle of a triangle is equal to the sum of the two opposite interior angles,** as angle BCD = angle A + angle B. THEOREM XVII. 77. If two triangles have two sides and the included... | |
| United States Naval Academy - 1904 - 980 pages
....^^^«(tO.-u (b) Given л- + xy = 70 and xy — y* =12, find .т and y. GEOMETRY. I. (a) Prove that **an exterior angle of a triangle is equal to the sum of the two opposite interior angles.** Define axiom and postulate, and give an example of each. Define trapezoid, trapezium, rhombus, and... | |
| Fletcher Durell - Geometry, Plane - 1904 - 382 pages
...its equal, ZA.and for /.BCE its equal, ZB, Ax. 8. ZA + /.B + /.BCA = 2 rt. A. 0. E. J>. 135. COR. 1. **An exterior angle of a triangle is equal to the sum of the two opposite interior angles.** 136. COR. 2. The sum of any two angles of a triangle is less than two right angles. 138. COR. 4. A... | |
| George Albert Wentworth - Geometry - 1904 - 496 pages
...COR. 7. In an equiangular triangle, each angle is one third of two right angles, or 60°. 137. COR. 8. **An exterior angle of a triangle is equal to the sum of the two opposite interior angles,** and therefore greater than either of them. PROPOSITION XIX. THEOREM. 138. The sum of two sides of a... | |
| Fletcher Durell - Geometry - 1911 - 553 pages
...LECD its equal, Z.4,and for LBCE its equal, LB, Ax. 8, /A+ ZB + Z BGA - 2 rt. Z . 0- EB 135o Con. 1. **An exterior angle of a triangle is equal to the sum of the two opposite interior angles.** 136o COR. 2. The sum of any two angles of a triangle is less than two right angles. 138. COR. 4. A... | |
| Cora Lenore Williams - Geometry - 1905 - 122 pages
...Theor. J. Straight lines parallel to the same straight line are parallel to each other.* Prop. 70. Any **exterior angle of a triangle is equal to the sum of the two opposite interior angles,** and the sum of the three interior angles is equal to two right angles. Prop. 71. The acute angles of... | |
| George Clinton Shutts - 1905 - 260 pages
...perimeter of a triangle is less than twice the sum of the medians. PROPOSITION XXVIII. 119, Theorem. **An exterior angle of a triangle is equal to the sum of** the opposite interior angles. Let ABC represent a triangle, D AC an erterior angle, and B and C the... | |
| Coast Artillery School (U.S.) - 1906 - 440 pages
.../—The determination of these circles depends on the two following propositions of geometry: namely, the **exterior angle of a triangle is equal to the sum of the two opposite interior angles;** and, secondly, an inscribed angle is measured by one-half the arc intercepted between its sides. Thus,... | |
| Joseph Claudel - Mathematics - 1906 - 758 pages
...acute angles of a right triangle are complementary (617, 633). 653. The exterior angle CBD (Fig. 41) **of a triangle is equal to the sum of the two opposite interior angles** A and C, and consequently greater than either of them. When the successive sides of a polygon are prolonged... | |
| International Correspondence Schools - Building - 1906 - 622 pages
...therefore, the third angle is equal to 180° - (44° 21' 30" + 110° 53' 45") = 24° 44' 45". Ans. (4) **An exterior angle of a triangle is equal to the sum of** the opposite-interior angles (Art. 68) . The sum of the opposite-interior angles is, therefore, 104°... | |
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