Explanation:
The equation of parabola if we are interested in the directrix either

or

Since this parabola is symmetric about the x axis, and we have a vertical directrix, we will use the second parabola equation

Here (h,k) is the vertex, so h and k are 0

What is the value of P.
The value of P is the displacement of the vertex to either the focus or directrix.
Since the directrix is right of the vertex, our p will be negative.
The distance between the vertex and directrix is -5.
Long story short: the shortest displacement between a line and a point is the perpendicular dispalcement , which would be -5.

Our answer is
