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Question 1158015: What is the standard and general equation of a parabola with vertex as (-1,2) and directrix of x=-3?
Found 2 solutions by josgarithmetic, MathLover1:
Answer by josgarithmetic(39620)   (Show Source):
You can put this solution on YOUR website! This means that focus is point (2,2). The parabola is points (x,y) equally distant from both the point (2,2) and the line x=-3.
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If you start with Distance Formula definition for parabola, you have
Algebra steps will be able to lead to  .
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Answer by MathLover1(20850)  (Show Source):
You can put this solution on YOUR website!
What is the standard and general equation of a parabola with vertex as ( , ) and directrix of  ?
recall:
The standard form is  , where the focus is ( ,  ) and the directrix is  .
If the parabola is rotated so that its vertex is (, ) and its axis of symmetry is parallel to the x-axis, it has an equation of  , where the focus is ( , ) and the directrix is .
The "general" form of equation of a parabola is the one you're used to,  unless the quadratic is "sideways", in which case the equation will look something like  .
vertex as (,)=> , 
directrix of
it has an equation of
we need to find  , using the directrix is and vertex
if given directrix of and , then
 ->The standard form
the "general" form of equation:
.......solve for 
 -> the general form
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