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What is the directrix of the parabola defined by 1/4(y+3)=(x-2)^2

User Fons MA
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This is a parabola which opens upwards and the directrix will be of the form
y = k

the general form is

4p(y - k) = (x - h)^2 we have:-

1/4(y + 3) = (x - 2)^2

so the vertex is at (2, -3)

4p = 1/4 so p = 1/16

so the focus will be at (2 , -2 15/16)

and directrix is y = -3 1/16
User Wix
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