| Andrew Bell - 1837 - Liczba stron: 240
...sides. 9. To bisect a parallelogram by a line drawn from a point in one of its sides. 10. A line joining **the middle points of two sides of a triangle, is parallel to the** base, and equal to the half of it. 11. The quadrilateral formed by joining the successiYe middle points... | |
| George Salmon - 1852 - Liczba stron: 316
...the internal bisector of the third angle : interpreted the other way, express that the line joining **the middle points of two sides of a triangle is parallel to the third side.** 5. We give now some examples of the use of these equations of the first degree. Ex. 1. Tiie bisectors... | |
| Euclides - 1853
...right angles. 10. To describe a square equal to the difference of two given squares. II. A line joining **the middle points of two sides of a triangle is parallel to the** "base, and equal to half of it. 12. To bisect a given parallelogram by a line drawn from a point in... | |
| 1856
...is an easy deduction, from any one of this series, that a straight line cutting off' equimultiples **of two sides of a triangle is parallel to the third side** ; and, conversely, a parallel to one side cuts off equimultiples of the other two sides. We need now... | |
| Euclides - 1860
...from P, and the line BC joining them is parallel to AE. EXERCISE XLIX. — THEOREM. The line joining **the middle points of two sides of a triangle is parallel to the** base, and equal to the half of it. Let ABC be a triangle, the line DE, that joins the middle points... | |
| James McDowell - 1867 - Liczba stron: 102
...and cut each other in a point of trisection. (EXERCISES, p. 3, No. 5.) Also 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. (1) Let AB CD be a rhombus. In the triangles ABC, ADC, the sides AB, AC are... | |
| Euclid, Isaac Todhunter - 1867 - Liczba stron: 400
...between these diagonals, then the area of the triangle is equal to the area of the quadrilateral. 106. **The straight line which joins the middle points of two sides of** any triangle is parallel to the base. . 107. Straight lines joining the middle points of adjacent sides... | |
| Richard Wormell - 1870 - Liczba stron: 16
...is frequently of use in solving problems on the intersection of lines : — "A straight line joining **the middle points of two sides of a triangle is parallel to the third** and equal to half the third." We will here give a few problems in which this fact is applied. 354.... | |
| Euclides - 1874
...(I. App., schol. 2), the corresponding areas are 1, 4, 9, 16, etc. Conversely. — 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. In the triangle ABC, let AB, AC be bisected in D and E. The line joining... | |
| Euclides - 1874
...Join PO and draw AQ- parallel to it. Then PQ shall bisect the triangle.] 53. 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. 54. The straight lines joining the middle points of the four sides of any... | |
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