Find the standard form of the equation of each parabola satisfying the given conditions. Focus: (0, -25) Directrix: y = 25
Solution:
Given directrix of y = 25 and focus (0, -25)
from any point (x, y) on the parabola the focus and directrix are equidistant
We are using distance formula √{(x - 0)2 + (y - (-25))2} = |y - 25|
Applying square on both sides
⇒ (x)2 + (y + 25)2 = (y - 25)2
⇒ (y + 25)2 - (y - 25)2 = -(x)2
⇒ y2 + 50y + 625 - (y2 - 50y + 625) = -x2
⇒ y2 + 50y + 625 - y2 + 50y - 625 = -x2
⇒ 100y = -x2
⇒ y = x2 /100
The quadratic equation created is y = x2/100.
Find the standard form of the equation of each parabola satisfying the given conditions. Focus: (0, -25) Directrix: y = 25
Summary:
The standard form of the equation of each parabola satisfying the given conditions. Focus: (0, -25) Directrix: y = 25 is y = x2/100.
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