Use the distance formula to find the equation of a parabola with the given focus and directrix . f(0,1) y=-1

For any point on the graph of a parabola, the distance to the focus and the distance to the directrix are equal.

The distance to the focus:


The distance to the directrix:
The directrix is a horizontal line, so the distance is the absolute value of the difference of the y-coordinates of the points.


The distances are equal: