What is the directrix y=-x^2-6x-7 ?

The directrix y=-x^2-6x-7 is y= 9/4

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directrix y=-x^2-6x-7

directrix

y = - x^{2} - 6 x - 7

y = \frac{9}{4}

Solution steps

Rewrite

y = - x^{2} - 6 x - 7

in the standard form

4 (- \frac{1}{4}) (y - 2) = (x - (- 3))^{2}

(h, k) = (- 3, 2), p = - \frac{1}{4}

Parabola is symmetric around the y-axis and so the directrix is a line parallel to the x-axis, a distance

- p

from the center

(- 3, 2)

y-coordinate

y = 2 - p

y = 2 - (- \frac{1}{4})

Refine

y = \frac{9}{4}

2 x^{2} - 13 x - 7

\frac{x ^{2} x ^{1}}{x}

(x + 1)^{2}

2 y^{2} + x + 20 y + 51 = 0

- 8 (x - 5) = (y + 1)^{2}