| Thomas Keith - Navigation - 1810 - 478 pages
...II. Hence every equilateral triangle is likewise equiangular, and the contrary. (I) COROLLARY III. A line drawn from the vertex of an isosceles triangle to the middle of the base, is perpendicular to, the base. For the two sides FB and BC are equal to the two... | |
| Thomas Keith - Navigation - 1826 - 504 pages
...II. Hence every equilateral triangle is likewise equiangular, and the contrary. (I) COROLLARY III. A line drawn from the vertex of an isosceles triangle to the middle of the base, is perpendicular to the base. For the two sides FB and вс are equal to the two... | |
| Thomas Keith - 1839 - 498 pages
...II. Hence every equilateral triangle is likewise equiangular, and the contrary. (315) COROLLARY III. A line drawn from the vertex of an isosceles triangle to the middle of the base, is perpendicular to the base. For the two sides FB and BC are equal to the two... | |
| Adrien Marie Legendre - Geometry - 1863 - 464 pages
...The angle BAD is equal to DAC, and BDA to CDA : hence, the last two are right angles. Consequently, a line drawn from the vertex of an isosceles triangle to the middle of the base, bisects the vertical angle, and is perpendicular to the base. PROPOSITION XII.... | |
| William Guy Peck - Conic sections - 1876 - 376 pages
...equal in all their parts, (P. 11). Hence, the angle A is equal to C, which was to be proved. Cor. 2. A line drawn from the vertex of an isosceles triangle to the middle of the base bisects the angle at the vertex, and is perpendicular to the base. For, from what... | |
| Moffatt and Paige - 1879 - 474 pages
...than two right angles. (21)- Draw a triangle which shall be equal to two other given triangles. (22) A line drawn from the vertex of an isosceles triangle to the middle point of the base is at right angles to it. (23) A line making equal angles with the sides of... | |
| William Chauvenet - Geometry - 1887 - 336 pages
...to the included angle EGF. Hence the triangles are equal, by Proposition VI. EXERCISE. Theorem.— A line drawn from the vertex of an isosceles triangle to the middle point of the base is perpendicular to the base, and bisects the vertical angle. PROPOSITION... | |
| James Andrew Blaikie, William Thomson - Geometry - 1891 - 160 pages
...the previous Ex. and § 1, Ex. 2. § 3. (BookworTc, EUCLID, I. 1-8.) 1. The straight line which joins the vertex of an isosceles triangle to the mid-point of the base, bisects the vertical angle and is perpendicular to the base. Let ABC be an isosceles triangle having... | |
| Charles Ambrose Van Velzer, George Clinton Shutts - Geometry - 1894 - 416 pages
...with the middle point of the base is perpendicular to the base, the triangle is isosceles. Ex. 24. Prove that a line drawn from the vertex of an isosceles triangle to the middle point of the base, (1) bisects the triangle, (2) bisects the vertical angle, (3) is perpendicular... | |
| John Henry Walsh - 1896 - 282 pages
...it necessary to draw the chord. Permit them to do so at first. 16. The pupils have already learned that a line drawn from the vertex of an isosceles triangle to the center of the base, is perpendicular to the base. The method employed in bisecting a line is practically... | |
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