Question
What are the focus and directrix of the parabola represented by the equation:8(y-6)=(x+2)squared?
Answers
Steve
You know that the standard parabola
x^2 = 4py
has focus at (0,p) and directrix at y = -p.
Your parabola has been shifted so its vertex is at (-2,6). 4p=8.
So, the focus is 2 above the vertex and the directrix is 2 below the vertex.
x^2 = 4py
has focus at (0,p) and directrix at y = -p.
Your parabola has been shifted so its vertex is at (-2,6). 4p=8.
So, the focus is 2 above the vertex and the directrix is 2 below the vertex.