x = y2
y = -x2
x = -y2
y = x2

Question

dumbsearch2 · Answer

I'm just wondering if any of these are parabolas with vertexes (0, 0) and a directrix x=1. When I try them, I see that they are all with a vertex of (0, 0), but the directrixs don't match. Any ideas, or am I doing something incorrectly?

directrix · Answer

Go over to http://www.wolframalpha.com/ and enter this phrase: "Focus x = y2" and click. A properties chart of the parabola will come up (scroll down to see it) and you can find test to see if this is the parabola that meets your criteria. If not, go to the second option and run it through the same process.

directrix · Answer

To help you get started, here is a link to the first option test: http://www.wolframalpha.com/input/?i=focus++x+%3D+y2

directrix · Answer

@dumbsearch2

dumbsearch2 · Answer

I did that, none of them seemed to match. @Directrix

directrix · Answer

Check to see if you posted the question correctly. Check against the problem source to be sure.

directrix · Answer

Did you make up the parabola equations yourself?

That is, is the actual question to find the equation of a parabola with directrex x = 1 and vertex (0,0)

directrix · Answer

I think this is it. You have to consider the value of 4p. Click and see what you think. @dumbsearch2 http://www.wolframalpha.com/input/?i=focus+x+%3D+-%281%2F4%29+y%5E2

dumbsearch2 · Answer

@Directrix 


Find the equation for the parabola with vertex (0, 0) and directrix x = 1.
	A.	x = y2
	B.	y = -x2
	C.	x = -y2
	D.	y = x2

directrix · Answer

@dumbsearch2   Look above your head at the Wolf link.

dumbsearch2 · Answer

I don't understand what you did, would you mind explaining it to me? @Directrix