SOLUTION: What is the directrix of the parabola described by this equation? y – 7 = (1/20)(x + 3)^2

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Question 1078577: What is the directrix of the parabola described by this equation?

y – 7 = (1/20)(x + 3)^2
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
y-7=%281%2F20%29%28x%2B3%29%5E2
20%28y-7%29=%28x%2B3%29%5E2
Vertex is (-3,7).
p, distance from directrix to vertex,
4p=20
p=5

DIRECTRIX: highlight%28y=2%29



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graph%28300%2C300%2C-8%2C8%2C-4%2C12%2C%281%2F20%29%28x%2B3%29%5E2%2B7%2C2%29