Axis of Symmetry of a Parabola

Every parabola has an axis of symmetry which is the line that runs down its center. This line divides the graph into two perfect halves.

In the picture of on the left, the axis of symmetry is the line x =1.

Problem 1) In the picture on the left, identify the axis of symmetry.
 answer  
It is the line x=2

Problem 2) What is the axis of symmetry of the parabola on the left?
  answer  
It is the line x = -1