Answer:

Step-by-step explanation:
The axis of symmetry can be calculated using the formula:

First we must determine a and b from the quadratic:
. This is in standard form, with the highest power first in descending order.
Standard form is also: 
If we compare this to the quadratic given, we can conclude that:

Substitute the values for a and b into the formula.

Multiply in the denominator.

Divide.

This can also be determined from the graph. It is the x-coordinate of the vertex or the maximum/minimum. It divides the quadratic into 2 symmetrical halves.