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Special Properties of Parabolas

The following figures illustrate examples of curves called parabolas.
Figure 1
Figure 2
Figure 3

Like hyperbolas, parabolas can open in various directions. They can open left, right, up, down or in any other direction.
Some parabolas are narrow, while other parabolas are wide.

One thing that is special about parabolas is that they only have one axis of symmetry. In each of the figures above, the axis of symmetry is drawn in blue.

Notice that the axis of symmetry is vertical if the parabola opens up or down (as in Figure 1) and horizontal if the parabola opens left or right (as in Figure 2).
Parabolas opening in other directions, as in Figure 3, will be studied briefly in the Extensions Module.

The point where the axis of symmetry cuts the parabola is called the vertex.

You can learn much more about parabolas in the Parabolas Module.

The following figures illustrate examples of curves called parabolas.
Figure 1	Figure 2	Figure 3
Like hyperbolas, parabolas can open in various directions. They can open left, right, up, down or in any other direction. Some parabolas are narrow, while other parabolas are wide.
One thing that is special about parabolas is that they only have one axis of symmetry. In each of the figures above, the axis of symmetry is drawn in blue.
Notice that the axis of symmetry is vertical if the parabola opens up or down (as in Figure 1) and horizontal if the parabola opens left or right (as in Figure 2). Parabolas opening in other directions, as in Figure 3, will be studied briefly in the Extensions Module.
The point where the axis of symmetry cuts the parabola is called the vertex.
You can learn much more about parabolas in the Parabolas Module.