Page:The Elements of Euclid for the Use of Schools and Colleges - 1872.djvu/364
1. On a given straight line describe an isosceles tri- angle having each of the sides equal to a given straight line.
2. In the figure of I. 2 if the diameter of the smaller circle is the radius of the larger, shew where the given point and the vertex of the constructed triangle will bo situated.
3. If two straight lines bisect each other at right an- gles, any point in either of them is equidistant from the extremities of the other.
4. If the angles ABC and ACB at the base of an isosceles triangle be bisected by the straight lines BD, CD, shew that DBC will be an isosceles triangle.
5. BAC is a triangle having the angle B double of the angle A. If BD bisects the angle B and meets AC at D, shew that BD is equal to AD.
6. In the figure of I. 5 if FC and BG meet at H shew that FH and GH are equal.
7. In the figure of I. 5 FC and BG meet at H, shew that AH bisects the angle BAC.
8. The sides AB,AD of a quadrilateral ABCD are equal, and the diagonal AC bisects the angle BAD: shew that the sides CB and CD are equal, and that the diagonal AC bisects the angle BCD.
9. ACB, ADB are two triangles on the same side of AB, such that AC is equal to BD, and AD is equal to BC, and AD and BC intersect at O: shew that the tri- angle AOB is isosceles.
10. The opposite angles of a rhombus are equal.
11. A diagonal of a rhombus bisects each of the angles through which it passes.