Ellipse

The point with respect to the ellipse is :

The sum of the focal distances of any point on the conic is

An arch of a bridge is semi-elliptical with major axis horizontal. If the length the base is meter and the highest part of the bridge is meter from the horizontal; the best approximation of the height of the arch. meter from the centre of the base is

The length of the semi-latus rectum of an ellipse is one thrid of its major axis, its eccentricity would be

Eccentricity of ellipse if it passes through point and is