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max2010maxim [7]
3 years ago
5

The directrix of a parabola is y=−4y=−4 . The focus of the parabola is (−2,−2)(−2,−2) .

Mathematics
1 answer:
Dennis_Churaev [7]3 years ago
5 0
Because the focus is (-2,-2) and the directrix is y = -4, the vertex is (-2,-3).

Consider an arbitrary point (x,y) on the parabola.
The square of the distance between the focus and P is
(y+2)² + (x+2)²
The square of the distance from the point to the directrix is
(y+4)²

Therefore
(y+4)² = (y+2)² + (x+2)²
y² + 8y + 16 = y² + 4y + 4 + (x+2)²
4y = (x+2)² - 12
y = (1/4)(x+2)² - 3

Answer: y= \frac{1}{4} (x+2)^{2} - 3

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I believe it is 0.5

Step-by-step explanation:

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3 years ago
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HELP!!!<br> 31) Find the measure of line segment DF.<br> A) 12<br> B) 13<br> C) 14<br> D) 15
oksian1 [2.3K]

Step-by-step explanation:

for the relationship of lengths of internal chords the product of both segments of a chord is equal for all intersecting chords.

in our case

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1 year ago
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