

Axis of Symmetry of a ParabolaAxis of Symmetry
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. Explore how the graph and equation relate to the axis of symmetry, by using our interactive program below. Identify Axis of Symmetry From GraphProblem 1) In the picture on the left, identify the axis of symmetry.
Problem 2) What is the axis of symmetry of the parabola on the left?
Axis of Symmetry FormulaThere are two different formulas that you can use to find the axis of symmetry. One formula works when the parabola's equation is in vertex form and the other works when the parabola's equation is in standard form.
Interactive Demonstration of Axis of Symmetry
Explore the relationship between the axis of symmetry and graph of a parabola by changing the values of a,b and c of the parabola plotter below Practice finding axis of symmetry from Vertex Form Equation
1) What is the following parabola's axis of symmetry
of
Practice finding axis of symmetry from Vertex Form Equation
y = (x + 3)² + 4
2) What is the axis of symmetry of the parabola y = (x – 3)² + 4
The axis of symmetry is the line x = 3 3) What is the axis of symmetry of y = (x–1)² + 1
1) What is the following parabola's axis of symmetry
of
y =x² −2x −3
x = b/2a Answer: the axis of symmetry is the line x = 1
1) What is the following parabola's axis of symmetry
of
y =x² −4x + 5 44
x = b/2a Answer: the axis of symmetry is the line x = 2 