What are the vertex focus and directrix of the parabola with the given equation y = 1/28(x - 4)2 - 5
Solution:
We know that the equation of a parabola is
(x - h)2 = 4p(y - k)
Where (h, k) is the vertex
(h, k + p) is the focus
y = k - p is the directrix
The given equation is
y = 1/28(x - 4)2 - 5
By further calculation
(x - 4)2 = 28 (y + 5)
From this we know that
(h, k) = (4, -5)
p = 7
So the focus (h, k + p) = (4, 2)
Directrix y = k - p = - 5 - 7 = -12
Therefore, the vertex is (4, -5), focus is (4, 2) and directrix is -12.
What are the vertex focus and directrix of the parabola with the given equation y = 1/28(x - 4)2 - 5
Summary:
The vertex, focus and directrix of the parabola with the given equation y = 1/28(x - 4)2 - 5 is (4, -5), (4, 2) and -12.
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