I will fan and medal anyone who can explain how to do this to me!!
Derive the equation of the parabola with a focus at (4, −7) and a directrix of y = −15. Put the equation in standard form.

f(x) = one sixteenthx2 − 8x + 11

f(x) = one sixteenthx2 − 8x − 10

f(x) = one sixteenthx2 − one halfx + 11

f(x) = one sixteenthx2 − one halfx − 10

Question

I will fan and medal anyone who can explain how to do this to me!!
Derive the equation of the parabola with a focus at (4, −7) and a directrix of y = −15. Put the equation in standard form. 

 f(x) = one sixteenthx2 − 8x + 11 

 f(x) = one sixteenthx2 − 8x − 10 

 f(x) = one sixteenthx2 − one halfx + 11 

 f(x) = one sixteenthx2 − one halfx − 10

anonymous · Answer

I need a full detail how to do this because I don't get it at all!

anonymous · Answer

@zzr0ck3r can you help me?

zzr0ck3r · Answer

http://hotmath.com/hotmath_help/topics/finding-the-equation-of-a-parabola-given-focus-and-directrix.html

zepdrix · Answer

Ahhh these are no fun.
I can show you how I would do it.
It's probably not the most elegant approach but it should help at least :P

zepdrix · Answer

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