ENGINEERING GRAPHICS-Drawing an ellipse using drafter

Example 1:A fixed point is 7.5cm. From a fixed point P moving i such a way that its distance from the fixed straight line is 2/3 times its distance from F.(1)Name the curve. (2) draw the tangent and normal.

PROCEDURE:

1. Draw X and Y axes. From the origin P,mark a point on the line at 75 mm. Divide this line into 5 equal parts each of length  15mm.
2. The 3rd point from the origin is marked as vertex V1 and the 5th point is marked as the focus F.
3. At F, draw 2 lines of degree 45 on both sides of V below x-axis.
4. Draw a straight line from V1 below x-axis. Join the point p and the point of intersection of the lines from V1 and F.This line meets the other line from F at any point.
5. Draw a straight line from that point to x-axis at V2.
6. Divide V1 V2 into 5-9 equal parts.
7. Mark these points as 1,2,....9.Draw straight lines from these points to the line which we drew from P.
8. Mark these points of intersection as 1',2',....9' respectively.
9. Now with 11' as radius and 1 as radius, cut arcs on both sides(above and below) of the line 11'.
10. With 22' as radius ,with 2 as radius cut arcs similarly on both sides.
11. Repeat the same for all the points.
12. At last join these points.