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Identify the focus, vertex and directrix from the equation: -16(y+1)=(x-2)²

User Shadfc
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Final answer:

The vertex of the parabola -16(y+1)=(x-2)² is (2, -1), the focus is (2, -5), and the directrix is the line y = 3.

Step-by-step explanation:

To identify the focus, vertex, and directrix from the given parabola equation -16(y+1)=(x-2)², we first rewrite it in standard form.

Given that the equation is in the format 4p(y-k)=(x-h)², where (h, k) is the vertex, we can determine that the vertex is (2, -1).

The coefficient of the (y+1) term is -16, so 4p = -16, giving us p = -4.

This means the focus, which lies p units from the vertex along the axis of symmetry, is at (2, -1+(-4)), which simplifies to (2, -5).

The directrix is a horizontal line (since the parabola opens up or down) that is located |p| units on the opposite side of the focus from the vertex.

Therefore, the directrix is y = -1-(-4) or y = 3.

User Muhammedv
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