Solution of question of cone 

CONE-

A cone is a surface generated by a variable straight line passing through a fixed point and satisfying one more condition i.e. intersecting a given curve or touching a given surface .
The fixed  point is called the vertex and the given curve(or guiding surface)of the cone. The variable straight line is known as the generator of the cone.
A cone whose equation is of second degree is known as quartic or quadratic cone.

solution of question of cone