Question

Axis of symmetry of f(x)=(x+3)^2-8

Answer 1

`x = - 3`

Step-by-step explanation

When a quadratic equation is in the vertex form,

`f(x) = a {(x - h)}^(2) + k`

the equation of axis of symmetry is simply

`x = h`

The given quadratic equation is

`f(x) = {(x + 3)}^(2) - 8`

We can rewrite this as

`f(x) = {(x - - 3)}^(2) - 8`

We now compare to

`f(x) = a {(x - h)}^(2) + k`

We have

`h = - 3 \: \: \: and \: \: k = - 8`

Therefore equation of axis of symmetry is:

`x = - 3`