Question

Compasses are used to construct circles. How can you construct an ellipse? Find out how

ellipses can be constructed (there are many interesting ways) and construct one.

Answer 1

The ellipse consists of a line which is neither a straight line (ruler) nor some arc of a circle (compass). It is however possible to draw an ellipse using two pins, a piece of rope and a pencil.

Pin one end of the rope to the paper and pin the other end on the paper as well, in such a way that the rope is not taut. Then pull the rope taut using the pencil and move the pencil around (while keeping the rope taut) to draw an ellipse.

Here is a compass and rule construction of of an ellipse with major axis aa and foci at F1=(−ae,0)F1=(−ae,0) and F2=(ae, 0)