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Using a directrix of y = −2 and a focus of (2, 6), what quadratic function is created?

here are the answers given
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f(x) = −one eighth (x − 2)2 − 2
f(x) = one sixteenth (x − 2)2 + 2
f(x) = one eighth (x − 2)2 − 2
f(x) = −one sixteenth (x + 2)2 − 2

User Mellie
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2 Answers

8 votes
I need help for my question please
User Mike Douglas
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11 votes

Answer:

f(x)=1/16(x-2)^2+2

Explanation:

The Equation can be written like this:

f(x) = 1/(4p)(x -h)^2 +(k-p)

where (h, k) is the focus, and p is half the distance between focus and directrix. Here, (h, k) = (2, 6) and p=(6-(-2))/2 = 4. So the equation is ...

f(x) = 1/16(x -2)^2 +2

User Ravenskater
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