Question 609543: When given the characteristics of the parabola, center at origin, and directrix at x=7. How do you find standard form? Answer by solver91311(24713) (Show Source):
When you say "center" at origin, I presume you mean the vertex is at the origin. A parabola doesn't have a "center" per se, which is a departure from the descriptions of the other three types of conics.
Since the directrix is a vertical line, the axis of the parabola is horizontal. Since the directrix must be outside of the parabola, i.e. the parabola opens away from the directrix, this paricular parabola opens to the left.
The problem with answering this question for you is that you don't define what you mean by "standard" form. There are two common forms for a parabola:
and
Some authors call the first one the "vertex" form and the second one the "standard" form. Other authors call the first one the "standard" form and the second one the "general form." So the question is, what does your teacher/instructor/professor and/or textbook author(s) mean by "standard" form?
John
My calculator said it, I believe it, that settles it
