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What is the equation of the parabola shown in the graph?





A.    y = -x^2/8 - x - 4

B.    y = -x^2/4 - 2x - 8

C.    y = -x^2/4 - 2x - 7

D.    y = -x^2/8 - x - 5

What is the equation of the parabola shown in the graphA y x28 x 4B y x24 2x 8C y x24 2x 7D y x28 x 5 class=

Respuesta :

c is the correct answer

Answer:

Option C

Step-by-step explanation:

The standard form is (x - h)2 = 4p (y - k), where the focus is (h, k + p) and the directrix is y = k - p.

The focus  is -4,-4 and the directrix is y=-2 therefore h=-4 and

-2=k-p and -4=k+p adding this last equations we get -6=2k therefor k=-3

and p=-1

we plug this in the equation of the standard form we get:

[tex](x+4)^{2} =-4(y+3)[/tex]

[tex]x^{2} +8x+16=-4y-12[/tex]

[tex]x^{2} +8x+28=-4y[/tex]

[tex]-\frac{x^{2}}{4}  -2x-7=y[/tex]

Option C

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