Question

What is the axis of symmetry for the graph of the following function?

y = -2(x + 4)2 + 7
The axis of symmetry is x =

Answer 1

-2x -8 * 2 + 7
-2x -16 + 7
-2x -9
-2x/-2x -9/-2x

X= 4 1/2 or 4.5

Answer 2

The axis of symmetry is x=-4.

Explanation:

If a quadratic function is defined as

`y=a(x-h)^2+k` .... (1)

then (h,k) is vertex, a is a constant and x=h is axis of symmetry.

The given quadratic function is

`y=-2(x+4)^2+7` ... (2)

On comparing (1) and (2), we get

`a=-2,h=-4,k=7`

It means the vertex of the parabola is at (-4,7) and the axis of symmetry is x=-4.

Therefore the axis of symmetry is x=-4.