What is the vertex form of y= x^2 -x - 11 ?

1 Answer
Sep 27, 2016

Vertex form is (x-1)^2=y+45/4.
The vertex or this parabola is V(1, -45/4)

Explanation:

The equation (x-alpha)^2=4a(y-beta) represents the parabola with

vertex at V( alpha, beta), axis VS along x = alpha, focus at

S(alpha, beta+a) and directrix as y=beta-a

Here, the given equation can be standardized as

(x-1)^2=y+45/4. giving a = 1'4, alpha = 1 and beta =-45/4.

Vertex is V(1, -45/4)

Axis is x=1.

Focus is S(1, -11).

Directrix is y=-49/4