<P> The line perpendicular to the directrix and passing through the focus ( that is , the line that splits the parabola through the middle ) is called the `` axis of symmetry '' . The point on the parabola that intersects the axis of symmetry is called the `` vertex '' , and is the point where the parabola is most sharply curved . The distance between the vertex and the focus , measured along the axis of symmetry , is the `` focal length '' . The `` latus rectum '' is the chord of the parabola which is parallel to the directrix and passes through the focus . Parabolas can open up , down , left , right , or in some other arbitrary direction . Any parabola can be repositioned and rescaled to fit exactly on any other parabola -- that is , all parabolas are geometrically similar . </P>
<P> The line perpendicular to the directrix and passing through the focus ( that is , the line that splits the parabola through the middle ) is called the `` axis of symmetry '' . The point on the parabola that intersects the axis of symmetry is called the `` vertex '' , and is the point where the parabola is most sharply curved . The distance between the vertex and the focus , measured along the axis of symmetry , is the `` focal length '' . The `` latus rectum '' is the chord of the parabola which is parallel to the directrix and passes through the focus . Parabolas can open up , down , left , right , or in some other arbitrary direction . Any parabola can be repositioned and rescaled to fit exactly on any other parabola -- that is , all parabolas are geometrically similar . </P>
what is the exact same distance from a parabola
what is the exact same distance from a parabola
focal length
focal length