| Association for the improvement of geometrical teaching - Geometry, Modern - 1884 - 150 pages
...points of the sides of a triangle divide it into four identically equal triangles. *Ex. 59. The straight **line joining the middle points of two sides of a triangle is** equal to half the base. Ex. 60. If a quadrilateral be formed by joining the middle points of the sides... | |
| Euclides - 1884 - 434 pages
...A DBC; which is impossible, since the one is a part of the other. ... AD is || BC. 1. The straight **line joining the middle points of two sides of a triangle is** || the third side, and = half of it. 2. Hence prove that the straight line joining the middle point... | |
| Edinburgh Mathematical Society - Mathematics - 1885 - 312 pages
...equivalent to HH, HK, HL, therefore HA is the resultant of HK, HL. Hence, HKAL is a parallelogram ; **the line joining the middle points of two sides of a triangle, is parallel to** and equal to half of the third side. 3. When P is at S, the centre of the circumscribing circle ABC,... | |
| George Bruce Halsted - Geometry - 1885 - 389 pages
...second side, it will bisect the third side ; and, inversely, the sect joining the midpoints of any **two sides of a triangle is parallel to the third side and equal to** half of it. 233. Three or more lines which intersect in the same point are said to be Concurrent. 234.... | |
| Euclid, John Casey - Euclid's Elements - 1885 - 340 pages
...Exercises. 1. Triangles and parallelograms of equal bases and altitudes are respectively equal. 2. The right **line joining the middle points of two sides of a triangle is** | arallel to the third ; for the medians from the extremities of the base to these points will each... | |
| Webster Wells - Geometry - 1886 - 392 pages
...a quadrilateral two of whose angles are right angles. PROPOSITION XLIV. THEOREM. 130. The straight **line joining the 'middle points of two sides of a...parallel to the third side and equal to one-half of it.** A In the triangle ABC, let B' be the middle point of AB and C" of AC. To prove that B'C' is parallel... | |
| George Albert Wentworth - Geometry, Analytic - 1886 - 334 pages
...(7, — 3) ? 52. Prove that the diagonals of a square are perpendicular to each other. 53. Prove that **the line joining the middle points of two sides of a triangle is parallel to the third side.** 55. Show that the three points (3a, 0), (0, 3b), (a, 2li) are in a straight line. 56. Show that the... | |
| George Albert Wentworth - 1886 - 322 pages
...(7, — 3) ? 52. Prove that the diagonals of a square are perpendicular to each other. 53. Prove that **the line joining the middle points of two sides of a triangle is parallel to the** thh-d side. 5.5. Show that the three points (3a, 0), (0, 3i), (a, 2K) are in a straight line. 56. Show... | |
| George Bruce Halsted - Geometry - 1886 - 394 pages
...second side, it will bisect the third side ; and, inversely, the sect joining the midpoints of any **two sides of a triangle is parallel to the third side and equal to** half of it. 233. Three or more lines which intersect in the same point are said to be Concurrent. 234.... | |
| William Chauvenet - Geometry - 1887 - 331 pages
...Suggestion. Draw DF parallel to AC. See now Proposition VII. and Proposition XXIX. 29. The straight **line joining the middle points of two sides of a triangle is parallel to the third side,** (v. Exercise 28.) 30. The three straight lines joining the middle points of the sides of a triangle... | |
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