Question

Determine the axis of symmetry for the function f(x) = 5(x + 1)2 − 8.

x = −8
x = 8
x = −1
x = 1

Answer 1

C.
`x=-1`

Explanation:

We have been given a function formula
`f(x)=5(x+1)^2-8`. We are asked to find the axis of symmetry for the given function.

We can see that our given function is a parabola in vertex form. We know that vertex from of parabola is
`y=a(x-h)^2+k`, where (h,k) represents vertex of parabola.

Let us convert our given function in vertex form as:

`f(x)=5(x-(-1))^2-8`

We know that axis of symmetry of a parabola is the equation of x-coordinate of vertex, which in form
`x=h`.

Since the x-coordinate of vertex is
`-1`, therefore, the axis of symmetry for the given function would be
`x=-1`.