| James Wallace MacDonald - Geometry - 1889 - 80 pages
...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 equal.** Proposition XXXV. A Theorem. 72. If two angles of a triangle are equal, the sides opposite these angles... | |
| James Wallace MacDonald - Geometry - 1894 - 76 pages
...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 equal.** COROLLARY. An equilateral triangle is also equiangular. Proposition XXXV. A Theorem. 72. If two angles... | |
| George Albert Wentworth - 1889 - 270 pages
...each. 39. Corollary. Two right triangles are equal if their legs are equal, each to each. 40. Theorem. **In an isosceles triangle the angles opposite the equal sides are equal.** 41. Corollary. An equilateral triangle is equiangular. 42. Theorem. If in a triangle two angles are... | |
| George Albert Wentworth - 1889 - 264 pages
...each. 39. Corollary. Two right triangles are equal if their legs are equal, each to each. 40. Theorem. **In an isosceles triangle the angles opposite the equal sides are equal.** 41. Corollary. An equilateral triangle is equiangular. 42. Theorem. If in a triangle two angles are... | |
| Edward Albert Bowser - Geometry - 1890 - 418 pages
...hypotenuse and an acute angle of the other. 107. COR. 2. Two right-angled triangles are equal when a **side and an acute angle of the one are equal respectively to** a side and homologoiis acute angle of the other. Proposition 23. Theorem. 108. Two triangles are equal... | |
| Education - 1890 - 776 pages
...four hypotheses regarding two straight lines from which they can be proved parallel. 4. Prove that **in an isosceles triangle the angles opposite the equal sides are equal.** 5. When are polygons mutually equiangular ? Explain the term homologous sides. 6. To what is the sum... | |
| Edward Albert Bowser - Geometry - 1890 - 420 pages
...triangle is 40° 14' 48", what is the value of the other acute angle ? Proposition 25. Theorem. 111. **In an isosceles triangle the angles opposite the equal sides are equal.** Hyp. Let ABC be an isosceles A having AC = BC. To prove /_ A = Z B. Proof. Draw the line CD from the... | |
| Thomas J. Foster - Coal mines and mining - 1891 - 456 pages
...greater side is opposite the greater angle, and the greater angle is opposite the greater side. 7. **In an isosceles triangle the angles opposite the equal sides are equal.** 8. In any triangle the sum of the three angles is equal to two right angles, or 180°. 9. If two angles... | |
| Seth Thayer Stewart - Geometry - 1891 - 428 pages
...XIV. 5§1. Theorem Many propositions fire equally true with spherical and plane triangles ; thus, I. **In an isosceles triangle, the angles opposite the equal sides are equal.** II. If two angles of a triangle are equal, the sides opposite are equal. III. If a triangle is equilateral,... | |
| George Bruce Halsted - Geometry - 1896 - 204 pages
...axis BD, ^ BDC will fall within 4 ADB, and therefore C must fall between A and B. 224. Corollary I. **In an isosceles triangle, the angles opposite the equal sides are equal.** 225. Corollary II. If two angles of a triangle are equal, the triangle is isosceles. 226. If we join... | |
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