| Euclides - 1870 - 270 pages
...square of a st. line is equal to four times the square of its half. 11. The st. line which bisects two sides of a triangle, is parallel to the third side, and equal to one half of it. 12. If two sides of a triangle be given, its area will be greatest when they contain... | |
| Richard Wormell - Geometry, Plane - 1870 - 304 pages
...DQ=D R. Consequently PR, which is equal to P D+DR, is equal to P D+D Q. Therefore EC=P D+D Q. 2. The line joining the middle points of two sides of a triangle is equal to half the third side, and is parallel to it. Let ABC be the triangle, D and E the middle points... | |
| Euclid, James Bryce, David Munn (F.R.S.E.) - Geometry - 1874 - 236 pages
...2, 3, 4, etc. (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...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 these points is parallel... | |
| Euclides - 1874 - 120 pages
...BC in 0. 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 quadrilateral... | |
| John Reynell Morell - 1875 - 220 pages
...corresponding height are given. EXERCISES ON BOOK III. 92. The straight line which joins the centres of two sides of a triangle is parallel to the third side, and equal to half that side. 93. The straight lines which join the centres of the consecutive sides of a quadrilateral... | |
| Aaron Schuyler - Geometry - 1876 - 384 pages
...parallelogram (82) ; AE = EC; hence, DE bisects AC. GEOMETRY.— BOOK I. 104. Corollaries. 1. Tlie straight line joining the middle points of two sides of a triangle is parallel to the third side and equal to its half. (?) 2. The straight line drawn from the middle point of one of the non-parallel sides of... | |
| Association for the improvement of geometrical teaching - Geometry, Modern - 1876 - 66 pages
...triangle parallel to the base passes through the middle point of the other side. COR. 2. The straight line joining the middle points of two sides of a triangle is parallel to the base. [Cor. i. and Rule of Identity.] SECTION 4. PROBLEMS. PROB. i. To bisect a given angle. PROB.... | |
| Robert Potts - Geometry - 1876 - 446 pages
...of AB andD C shall divide the quadrilateral into two equal parts. 8. The straight line, which joins the middle points of two sides of a triangle, is parallel to the base. 9. If a straight line be divided into any two parts, the square on the whole line is equal to... | |
| Richard Wormell - 1876 - 268 pages
...the middle point of a side of a triangle parallel to the base it will bisect the other side. 43. The line joining the middle points of two sides of a triangle is equal to half the third side and is parallel to it. 44. If from points in the base of an isosceles... | |
| Elias Loomis - Conic sections - 1877 - 458 pages
...the angles of the square. PROPOSITION III. 5. The straight line which joins the middle points of any two sides of a triangle is parallel to the third side, and is equal to one half of that side. In the triangle ABC, let D be the middle point of AB, and E the... | |
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