| John Wesley Young, Albert John Schwartz - Geometry, Modern - 1915 - 248 pages
...of the triangle. Thus ' 73 C "^ DCA (Fig. 73) is an exterior angle of PLANE GEOMETRY 186. THEOREM. An exterior angle of a triangle is equal to the sum of the opposite interior angles. D FIG. 74. (The proof is left to the student.) 187. COBOLLABY. An exterior... | |
| Edward Rutledge Robbins - Geometry, Plane - 1915 - 282 pages
...the other vertices are the opposite interior angles. [ZA and Z C.] PROPOSITION XXXIII. THEOREM 102. An exterior angle of a triangle is equal to the sum of the opposite interior angles. Given : A ABC ; exterior Z ABD. To Prove : Z ABD = ZA + Z C. ^" ~ ""... | |
| Claude Irwin Palmer, Daniel Pomeroy Taylor - Geometry, Plane - 1915 - 336 pages
...two right angles. Prolong AC to F . Draw CE II AB. ZA = Zz. § 133 § 132 §60 §111 144. Theorem. An exterior angle of a triangle is equal to the sum of the opposite interior angles, and is therefore greater than either of them. §105 Why? .-. ZBCF > ZA... | |
| William Betz - Geometry - 1916 - 536 pages
...+ Zq Ax. 2 4. But Zp + Z o + Z q = a st. Z. Why ? .-.Zm + Zo + Zn = ast. Z. Ax. 1 181. COROLLARY 1. An exterior angle of a triangle is equal to the sum of the two remote interior angles, and is therefore greater than either of them. 182. COROLLARY 2. If... | |
| Ernst Rudolph Breslich - Logarithms - 1917 - 408 pages
...384. The sum of the exterior angles of a triangle, taking one at each vertex, is 360°. (115) 385. An exterior angle of a triangle is equal to the sum of the two remote interior angles. (118), (199) 386. If the angles of one triangle are respectively equal... | |
| Claude Irwin Palmer, Daniel Pomeroy Taylor - Geometry - 1918 - 460 pages
...Prolong AC to F. Draw CE-\\ AB. Z4 = Zz. § 133 §132 ' = 180°. §60 = 180°. §111 144. Theorem. An exterior angle of a triangle is equal to the sum of the opposite interior angles, and is therefore greater than either of them. §105 Why? .'. ZBCF>ZA... | |
| Herbert Ellsworth Slaught, Nels Johann Lennes - Geometry, Plane - 1918 - 360 pages
...to an acute angle of another right triangle, the remaining acute angles are equal. 160. COROLLARY 4. An exterior angle of a triangle is equal to the sum of the two opposite interior angles. Suggestion. Zl + Z2+Z3 = 2rt. A, Euclid (about 330-275 BC-), a famous... | |
| Herbert Ellsworth Slaught - 1918 - 344 pages
...to an acute angle of another right triangle, the remaining acute angles are equal. 160. COROLLARY 4. An exterior angle of a triangle is equal to the sum of the two opposite interior angles. Suggestion. Zl + Z2+z3 = 2rt. A, Euclid (about 330-275 BC). a famous... | |
| Claude Irwin Palmer - Geometry, Solid - 1918 - 192 pages
...Theorem. The sum of the angles of a triangle is equal to 180°, or two right angles. § 144. Theorem. An exterior angle of a triangle is equal to the sum of the opposite interior angles, and is therefore greater than either of them. § 146. Theorem. In a triangle,... | |
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