Find equation of parabola with focus and directrix

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SUMMARY

The equation of the parabola with focus at (0, -4) and directrix y = -2 is derived as y + 3 = -1/4(x)². The vertex is calculated as the midpoint between the focus and the directrix, resulting in the vertex at (0, -3). The relationship D1 = D2, where D1 is the distance from the focus to any point on the parabola and D2 is the distance from that point to the directrix, is crucial for understanding the parabola's properties.

PREREQUISITES
  • Understanding of parabolic geometry
  • Knowledge of the vertex form of a parabola
  • Familiarity with distance formulas in coordinate geometry
  • Basic graphing skills for plotting parabolas
NEXT STEPS
  • Study the derivation of the vertex form of a parabola
  • Learn about the properties of conic sections, specifically parabolas
  • Explore the concept of focus and directrix in conic sections
  • Practice graphing parabolas using different focuses and directrices
USEFUL FOR

Students studying algebra and geometry, educators teaching conic sections, and anyone interested in mastering the properties of parabolas.

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Homework Statement


Find the equation of the parabola with focus (0, -4) and directrix y = -2

i barely understand this thing. i mean how do i find the vertex.
the book says D1 = focus to any point on the graph, and D2= the point on the graph to the directrix. and D1 = D2. how do i graph if i don't know the vertex

Homework Equations





The Attempt at a Solution


answer: y + 3 = -1/4(x)2
 
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The vertex is the midpoint between the focus and the directrix.
 

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