| Andrew Bell - Euclid's Elements - 1837 - 290 pages
...of its 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 - Conic sections - 1852 - 338 pages
...present method, prove that three points are in one right line. Thus the equations a + /3=0, /3 - y = 0, y + a = 0, interpreted one way, express that two...use of these equations of the first degree. Ex. 1. Tiie bisectors of the sides of a triangle meet in a point; viz., in the point a + /3 + ? = 0. For this... | |
| George Salmon - Conic sections - 1852 - 329 pages
...interpreted in the present method, prove that three points are in one right line. Thus the equations interpreted one way, express that two external bisectors...use of these equations of the first degree. Ex. 1. The bisectors of the sides of a triangle meet in a point; viz., in the point a + j3 + y = 0. of the... | |
| Euclides - 1853 - 146 pages
...to four 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... | |
| Education - 1856 - 732 pages
...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 pages
...therefore equidistant 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... | |
| Euclides - 1860 - 288 pages
...given point, and such, that the line joining them shall be parallel to the other given line. 49. A line joining the middle points of two sides of a triangle, is parallel to the base, and equal to the half of it. • I 50. The quadrilateral formed by joining the successive middle... | |
| Mathematics - 1865 - 132 pages
...B + ft cos3 B + y cos C sin2 B) (aa + bft + cy). 3. To find the equation to the circle described on the line joining the middle points of two sides of a triangle. Let D, F (Fig. 3) be the middle points of BC, BA ; join DF and draw the perpendiculars DH, FK. Then... | |
| 1865 - 128 pages
...B + ft cos3 B + 7 cos C sin2 B) (aa + i0 + C7). 3. To find the equation to the circle described on the line joining the middle points of two sides of a triangle. Let D, F (Fig. 3) be the middle points of BC, BA; join DF and draw the perpendiculars DH, FK. Then... | |
| James McDowell - Mechanics - 1867 - 120 pages
...same point 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... | |
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