Quetion to find the equation of a parabola i want check

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To find the equation of a parabola using the distance formula, the focus and directrix must be correctly identified. For the first case, with a directrix at x = -4 and a focus at (2,2), the provided equation was incorrect, as it suggested y = -4. In the second case, with a directrix at x = 2 and a focus at (6,-4), the parabola must open horizontally, but the response indicated it opened upward, which is incorrect. Additionally, the vertex must be calculated as the midpoint between the focus and directrix, and the directrix should be included in the graph for clarity. Correctly applying these principles is essential for accurately determining the parabolic equations.
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Hi all

Use the definition of a parabola and the distance formula to find the equation of a parabola with

a ) directix x = -4 and focus (2,2 )
B ) directix x = 2 and focus (6,-4 )

my answer :

383986876.jpg


206452772.jpg
 
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r-soy said:
Hi all

Use the definition of a parabola and the distance formula to find the equation of a parabola with

a ) directix x = -4 and focus (2,2 )
B ) directix x = 2 and focus (6,-4 )
Your work for a) is not consistent with the requirements above. In your work for a, you have y = -4. Which is it?

For b), because the directrix is x = 2, the parabola has to open to the left or right. Yours opens upward, which is wrong.

Also, you don't draw the directrix for either parabola in your graph. The vertex of the parabola is halfway between the directrix and focus, so you can use the directrix and focus to figure out where the vertex is.

r-soy said:
my answer :

383986876.jpg


206452772.jpg
 
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