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2.7 Constructing Ellipse

a. Construct an ellipse rectangle method

Steps:

1. Draw a rectangle taking major and minor axes as sides.
2. In this rectangle draw both axes as perpendicular bisectors of each other.
3. For construction, select the upper left part of rectangle. Divide vertical small side

and horizontal long side into the same number of equal parts. (here divided into four
parts)
4. Name those as shown.
5. Now join all vertical points 1,2,3,4 to the upper end of the minor axis. And all
horizontal points i.e 1,2,3,4 to the lower end of the minor axis.
6. Then extend the C-1 line up to D-1 and mark that point. Similarly extend C-2, C-3, C-
4 lines up to D-2, D-3 and D-4 lines.
7. Mark all these points properly and join all along with ends A and D in the smooth
possible curve. Do similar construction in right side part along with the lower half of
the rectangle. Join all points in a smooth curve.
It is a required ellipse.