Assertion: parabola's directrix | /r/HasProperty | the line
Facets:
value: at infinity
type: OTHER
value: outside the u-shaped graph
type: LOCATION
value: always
type: DEGREE
value: at y=-2
type: OTHER
Source sentences:
text: The directrix is the line y
text: Directrix is a line that is perpendicular to the axis of symmetry of a parabola.
text: The directrix is the line
text: Therefore, the focus is (0, 1/4a) = (0, 1/[4(-1/2)]) = (0, -1/2) and the directrix is the line y
text: In the graph below, y=1/8*x2, the focus is the point at (0,2), and the directrix is the line at y=-2.
text: F and the directrix is the line L.)
text: Let F be the point (m,n), and the directrix be the line y
text: Let F be the point (m,n), and the directrix be the line y
text: The directrix is the line y=-p.
text: The focus is always a point inside the u-shaped graph, and the directrix is always a line outside the u-shaped graph.
text: directrix (dih-RECK-triks): a line from which distances are measured in forming a conic; the plural form is "directrices" (dih-RECK-trih-seez).
text: If the distance to the focus is fixed and the directrix is a line at infinity, so the eccentricity is zero, then the conic is a circle.
text: So if the focus is down -3/2 from the vertex, then the directrix is a line that is up 3/2 from the vertex.
text: So the directrix will be a line, x = 13/4.