How do I find the vertex, focus, and directrix of a parabola?

Arrange your equation in this form:



or



The vertex is (x,k); the focus is (h, k+p); the directrix is y=k-p where p is the distance from the vertex to the focus.

You can also search;

Parabola - Wikipedia, the free encyclopedia

Basically, you put your equation into a general form.



or



vertex = (h,k)
focus = (h,k + p)
directrix y = k − p. p is the distance from the vertex to the focus


Link to: Parabola - Wikipedia, the free encyclopedia