 | Andrew Bell - 1837 - 290 σελίδες
...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 - 338 σελίδες
...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 - 146 σελίδες
...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 - 732 σελίδες
...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 - 142 σελίδες
...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 - 120 σελίδες
...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 - 426 σελίδες
...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 - 304 σελίδες
...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.... | |
 | Euclid, James Bryce, David Munn (F.R.S.E.) - 1874 - 236 σελίδες
...(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 - 120 σελίδες
...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... | |
| |
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. 
