let us first construct ellipse by focus directrix method consider the given data the distance of the focus from the directrix is equal to 50 mm and eccentricity is 2x3 also draw tangent and normal at any point Q on the curve using directrix step 1 draw a vertical line a B and from Point C draw a horizontal line step two mark point F 50mm from Point C and divide the CF into five equal parts sum of numerator and denominator step 3 mark the vertex V on the second division point from F step four from V draw a perpendicular line and mark point E such that V F equals V e join ze and extend it Step five derive the line in equal number of parts the right of F step 6 now drop appendicular from this respective points step 7 measuring distance 1 1 - draw an arc from point F on either side similarly measuring 2 2 - draw an arc from point F on either side similarly measure 4 point 3 4 and so on and draw an arc on either side step 8 with the help of the French curve connect the points to get the required ellipse let us consider point Q anywhere on the ellipse step 9 join point Q - f step 10 construct 90 degree angle with this line at Point F and extend the line to meet directrix at T step 11 join this point to Q and extend it this line is tangent to the ellipse at Point Q step 12 point q draw a perpendicular line this line is normal to the curve this is the required ellipse you