SOLUTION: problem: write the eqation in standard form for each parabola. vertex (0,0), Focus (-8,0) I know the proper equation. I just do not know which. the one with y= or x=. also when

Algebra ->  Quadratic-relations-and-conic-sections -> SOLUTION: problem: write the eqation in standard form for each parabola. vertex (0,0), Focus (-8,0) I know the proper equation. I just do not know which. the one with y= or x=. also when      Log On


   

Question 399871: problem: write the eqation in standard form for each parabola.
vertex (0,0), Focus (-8,0)
I know the proper equation. I just do not know which. the one with y= or x=. also when given the foci how do you get the directix?
Found 2 solutions by robertb, Tatiana_Stebko:
Answer by robertb(5830) About Me  (Show Source):
Answer by Tatiana_Stebko(1539) About Me  (Show Source):
You can put this solution on YOUR website!
If Vertex (0;0),Focus (p;0) then the equation in standard form for parabola is y%5E2=4%2Ap%2Ax(directrix is line x=-p)
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Focus (-8;0) p=-8
y%5E2=4%2A%28-8%29%2Ax
y%5E2=-32x
if you ask about directrix: if Focus (-8;0) directrix is line x=8
.
.
If Vertex (0;0),Focus (0;p) then the equation in standard form for parabola is x%5E2=4%2Ap%2Ay(directrix is line y=-p)