How do you find the vertex, focus and directrix of -48x = y^2 48x=y2?

1 Answer
Sep 8, 2016

(1) the Vertex is, (0,0)(0,0).

(2) Focus is (a,0)=(-12,0)(a,0)=(12,0), and,

(3) Eqn. of Directrix is : x+a=0, i.e., x=12:x+a=0,i.e.,x=12.

Explanation:

Comparing with the Standard Eqn. y^2=4ax, a=-12y2=4ax,a=12.

Hence, (1) the Vertex is, (0,0)(0,0).

(2) Focus is (a,0)=(-12,0)(a,0)=(12,0), and,

(3) Eqn. of Directrix is : x+a=0, i.e., x=12:x+a=0,i.e.,x=12. graph{y^2=-48x [-118.6, 118.55, -59.2, 59.3]}