 | John Henry Tanner, Joseph Allen - 1898 - عدد الصفحات: 466
...equal length, bisect each other, and are at right angles. 10. Prove analytically that the line joining the middle points of two sides of a triangle is parallel to the third side and equal to half its length. Find the locus of the vertex of a triangle whose base is 2 a and the... | |
 | Seymour Eaton - 1899 - عدد الصفحات: 362
...into which a parallelogram is divided by its diagonals are equal to one another. • 3. Prove that the straight line which joins the middle points of two sides of a triangle is parallel to the base. Lesson No. 18 PROPOSITION 40. THEOREM Equal triangles, on equal bases in the same straight line,... | |
 | George Albert Wentworth - 1899 - عدد الصفحات: 246
...is parallel to the base of a triangle and bisects one side, it bisects the other side also. 189. The line which joins the middle points of two sides of a triangle is parallel to the third side, and is equal to half the third side. 190. The median of a trapezoid is parallel to the bases, and is... | |
 | George Albert Wentworth - 1899 - عدد الصفحات: 498
...they intercept equal parts on the transversal AC; that is, the line DE bisects AC. 189. COB. 2. The line which joins the middle points of two sides of a triangle is parallel to the third side, and is equal to half the third side. A line drawn through D, the middle point of AB, II to BC, passes... | |
 | George Albert Wentworth - 1899 - عدد الصفحات: 278
...they intercept equal parts on the transversal AC; that is, the line DE bisects AC. 189. COR. 2. The line which joins the middle points of two sides of a triangle is parallel to the third side, and is equal to half the third side. A line drawn through D, the middle point of AB, II to BC, passes... | |
 | William James Milne - 1899 - عدد الصفحات: 404
...lines drawn between the same two points, which by Ax. 12 is impossible. Consequently, the line joining the middle points of two sides of a triangle is parallel to the third side. Proposition XLIII 160. Draw a trapezoid and a line connecting the middle points of the non-parallel... | |
 | Charles Austin Hobbs - 1899 - عدد الصفحات: 266
...when the two diagonals and the included angle are given. Proposition 64. Theorem. 76. The line joining the middle points of two sides of a triangle is parallel to the third side, and is equal to one half the third side. B 57 Conclusion. DE is II to BC, and DE = \ BC. Proof. Draw... | |
 | William James Milne - 1899 - عدد الصفحات: 258
...lines drawn between the same two points, which by Ax. 12 is impossible. Consequently, the line joining the middle points of two sides of a triangle is parallel to the third side. Proposition XLIII 160. Draw a trapezoid and a line connecting the middle points of the non-parallel... | |
 | Webster Wells - 1899 - عدد الصفحات: 450
...AC. (Sum of A at B = 2 rt. A.) A MISCELLANEOUS THEOREMS. PROP. XLVII. THEOREM. 130. The line joining the middle points of two sides of a triangle is parallel to the third side, and equal to one-half of it. B Given line DE joining middle points of sides AB and AC, respectively,... | |
 | Webster Wells - 1899 - عدد الصفحات: 424
...AC. (Sum of A at B = 2 rt. A.) A MISCELLANEOUS THEOREMS. PROP. XLVII. THEOREM. 130. The line joining the middle points of two sides of a triangle is parallel to the third side, and equal to one-half of it. Given line DE joining middle points of sides AB and AC, respectively,... | |
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The straight line joining the middle points of two sides of a triangle is parallel to the third side and equal to half of it 46 INTERCEPTS BY PARALLEL LINES. 
