Constructions (accurate drawings) can be made using a ruler, a pair of compasses and a pencil. A line which cuts an angle into two equal side angles is called an angle bisector. In geometry a ...

In Chapter 3 it was asserted that (1) at any point on an ellipse the bisector of the bistatic angle is orthogonal to the tangent to the ellipse and (2) the tangents of concentric hyperbolas are ...