 | 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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In an isosceles triangle the angles opposite the equal sides are equal. 
