What is the directrix y=-x^2-4x-3 ?

The directrix y=-x^2-4x-3 is y= 5/4

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directrix y=-x^2-4x-3

directrix

y = - x^{2} - 4 x - 3

y = \frac{5}{4}

Solution steps

Rewrite

y = - x^{2} - 4 x - 3

in the standard form

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

(h, k) = (- 2, 1), 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

(- 2, 1)

y-coordinate

y = 1 - p

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

Refine

y = \frac{5}{4}

y = 2 x^{2} + 3 π

x = (2 y - 1) (5 y - 6)

+ 2 (x + 1)^{2} - 3

x^{2} - 6 y = 0

- 8 (y - 3) = (x + 4)^{2}