# How do you find the axis of symmetry, and the maximum or minimum value of the function #y = x^2 + 4x + 4#?

##### 1 Answer

Feb 10, 2016

The axis of symmetry is x = -2

The minimum of the function is 0

#### Explanation:

The formula for the axis of symmetry is given by

where the quadratic is

Therefore just plug the values in:

Now that we have the x value, we can plug this in to find the y value, which will always be either a max or a min for the axis of symmetry.

We find that y = 0.

If a is positive, there will be a min

If a is negative, there will be a max

(just think back to the parent function

Therefore 0 is the minimum value.

The axis of symmetry is x = -2