Question

I don't understand how to solve this, can someone explain?

Answer 1

Hello!

The answer is:

$x=-2$

Why?

The axis of symmetry of the parabola is a line that cuts the parabola in two symmetric halves.

We can find the axis of symmetry of any parabola using the following formula:

$x=\frac{-b}{2a}$

We are given the parabola:

$f(x)=2x^{2} +8x+8$

Where,

$a=2\\b=8\\c=8$

So, finding the axis of symmetry we have:

$x=\frac{-b}{2a}=\frac{-8}{2*2}=\frac{-8}{4}=-2$

So, the axis of symmetry of the parabola is:

$x=-2$

Have a nice day!