 | Euclides - 1845 - 546 pages
...are together one-third of the squares of the sides of the triangle. 27. Prove that the square of any straight line drawn from the vertex of an isosceles triangle to the base, is less than the square of a side of the triangle by the rectangle contained by the segments... | |
 | Johann Georg Heck - Encyclopedias and dictionaries - 1851 - 712 pages
...is known that every line hanging plumb must be perpendicular to a horizontal plane, and that a line from the vertex of an isosceles triangle to the middle of the base, will be perpendicular to the base. Upon these principles rests the determination of a horizontal position... | |
 | 1851 - 716 pages
...is known that every line hanging plumb must be perpendicular to a horizontal plane, and that a line from the vertex of an isosceles triangle to the middle of the base, will be perpendicular to the base. Upon these principles rests the determination of a horizontal position... | |
 | Adrien Marie Legendre - Geometry - 1852 - 436 pages
...that is to say, has all its angles equal. ADC; hence, tlie latter two are right angles. Therefore, the line drawn from the vertex of an isosceles triangle to the middle point of the base, divides the angle at the vertex into two equal parts, and is perpendicular to the... | |
 | Charles Davies - Geometry - 1854 - 436 pages
...is equal to DAC, and BDA to 30 GEOMETRY. ADC; hence, the latter two are right angles. Therefore, ike line drawn from the vertex of an isosceles triangle to the middle point of the base, div1des the angle at the vertex into two equal parts, and is perpendicular to the... | |
 | Peter Nicholson - Cabinetwork - 1856 - 518 pages
...61. COROLLARY 1. — Hence every equilateral triangle is also equiangular. в с 62. COROLLARY 2. — A straight line drawn from the vertex of an isosceles triangle to the middle of the base will bisect the vertical angle, and be perpendicular to the base. THEOREM 12. 63. If two angles of... | |
 | Johann Georg Heck - Encyclopedias and dictionaries - 1860 - 332 pages
...is known that every line hanging plumb must be perpendicular to a horizontal plane, and that a line from the vertex of an isosceles triangle to the middle of the base, will be perpendicular to the base. Upon these principles rests the determination of a horizontal position... | |
 | Robert Potts - Geometry, Plane - 1860 - 380 pages
...is equivalent to twice the rectangle under the extreme segments. V. 37. Prove that the square on any straight line drawn from the vertex of an isosceles triangle to the base, is less than the square on a side of the triangle by the rectangle contained by the segments... | |
 | Euclides - 1862 - 140 pages
...straight line which bisects the vertical angle of an isosceles triangle, bisects also the base. 3. The straight line drawn from the vertex of an isosceles triangle to the point of bisection of the base, bisects the vertical angle, and is perpendicular to the base. 4. In... | |
 | Euclides - 1864 - 448 pages
...is equivalent to twice the rectangle under the extreme segments. V. 37. Prove that the square on any straight line drawn from the vertex of an isosceles triangle to the base, is less than the square on a side of the triangle by the rectangle contained by the segments... | |
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Hence a straight line drawn from the vertex of an isosceles triangle, to the middle of the base, is perpendicular to that base, and divides the vertical angle into two equal parts. 
