| Andrew Bell - Euclid's Elements - 1837 - 290 pages
...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 of the sides of... | |
| Thomas Holliday - Surveying - 1838 - 404 pages
...constructed, and the opposite angle to the base is called the vertex. 4. A straight line bisecting any two sides of a triangle is parallel to the base, and equal to one half of it, and the triangle cut off is equal to one fourth of the original triangle. See fig.... | |
| Euclides - 1853 - 146 pages
...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 one of its sides. 13. To bisect... | |
| Euclides - 1860 - 142 pages
...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 D, E, of two of its... | |
| Euclides, James Hamblin Smith - 1879 - 376 pages
...but AD is || to BF, .: AD is || to BF. QED Ex. 1. The straight line, joining the points of bisection of two sides of a triangle, is parallel to the base, and is equal to half the base. PROPOSITION XLI. THEOREM. If a parallelogram and a triangle be upnn the... | |
| Euclides - 1883 - 176 pages
...QED 99. The diagonals of a parallelogram bisect each other. 100. The line joining the middle points of two sides of a triangle is parallel to the base, and equal to half the base of the triangle. 101. The lines joining the middle points of the adjacent sides of a quadrilateral... | |
| Education - 1902 - 730 pages
...the midpoints as stated are parallel to and equal to one-half of each diagonal, because the join of the midpoints of two sides of a triangle is parallel to the third side and equal to half of it. Also, the parallelogram equals one-half of the original quadrilateral... | |
| Euclides - 1884 - 182 pages
...BEC are equal ; show that AH and CD are parallel. 3. The straight line which joins the middle Jpoints of two sides of a triangle is parallel to the base and equal to half of it. 4. Straight lines which join the middle points of adjacent sides of a quadrilateral form a parallelogram.... | |
| Edward Mann Langley, W. Seys Phillips - 1890 - 538 pages
...diagonals of a quadrilateral bisect each other it must be a parallelogram. Ex. 65. — The join of the mid-points of two sides of a triangle is parallel to the base and equal to half of it. Ex. 66.— The straight line through the mid-point of one side of a triangle parallel to another side... | |
| Wooster Woodruff Beman, David Eugene Smith - Geometry - 1895 - 344 pages
...parallel passes through the vertex, th. 27 or cor. 1 proves it. Draw the figure. 3. The line joining the mid-points of two sides of a triangle is parallel to the third side. For if not, suppose through the mid-point of one of those sides a line is drawn parallel... | |
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