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Write an equation of the parabola with vertex (0, 0) and directrix x=2.

User Tree
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2 Answers

2 votes

Final answer:

The equation of the parabola with vertex (0, 0) and directrix x = 2 is x² = -8y, which is derived from the general form of the parabola equation using the vertex and the distance to the focus.

Step-by-step explanation:

To find the equation of a parabola with vertex at (0, 0) and directrix x = 2, we use the fact that the distance from any point P(x, y) on the parabola to the focus is the same as the distance from P to the directrix. Since the vertex is at the origin and the directrix is a vertical line, the focus would be at (-2, 0). The general form of the equation of a parabola is (x - h)² = 4p(y - k), where (h, k) is the vertex of the parabola and p is the distance between the vertex and the focus.

In this case, since the vertex is (0, 0) and the focus is at (-2, 0), p is -2 (p is negative because the parabola opens to the left). Therefore, we have x² = -8y. This is the equation of our parabola.

User Mmeany
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4 votes

Answer:

y² = -8x

Step-by-step explanation:

directrix x=2 and vertex (0, 0) means focus: (-2, 0)

also means the distance from the origin to the focus: a=2

y² = -4ax

y² = -4×2x

y² = -8x

User Mawimawi
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