Answer
a)
A parabola is the set of all points in a plane such that the distance from a line called the directrix and the distance from a fixed point called focus are equal. In other words, a parabola is the set of all points that are equidistant from the directrix and the focus.
b)
The equation of a parabola with focus $(0,p)$ and directrix $y= -p$ is: $x^{2} = 4py$; if the focus is $(p,0)$, then the equation will be: $y^{2} = 4px$.
Work Step by Step
a)
Definition of a plane.
b)
Definition of a parabola.
