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A) x = -2
B) y =2
C) y= -2

A) x = -2 B) y =2 C) y= -2-example-1
User Poku
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Answer:

Explanation:

This is a positive parabola so it opens upwards. The equation for the directrix of this parabola is y = k - p. k is the second number in the vertex of the parabola which is (0, 0), but we need to solve for p.

The form that the parabola is currently in is


y=a(x-h)^2+k so that means that
a=(1)/(8). We can use that to solve for p in the formula


p=(1)/(4a) so


p=(1)/(4((1)/(8)) ) which simplifies to


p=(1)/((1)/(2) ) which gives us that

p = 2. Now to find the directrix:

y = k - p becomes

y = 0 - 2 so

y = -2, choice A.

User Profpatsch
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