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

The directrix y=x^2-4x-4 is y=-33/4

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directrix y=x^2-4x-4

directrix

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

y = - \frac{33}{4}

Solution steps

Rewrite

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

in the standard form

4 \cdot \frac{1}{4} (y - (- 8)) = (x - 2)^{2}

(h, k) = (2, - 8), 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, - 8)

y-coordinate

y = - 8 - p

y = - 8 - \frac{1}{4}

Refine

y = - \frac{33}{4}

+ y^{2} - y - x + 1 = 0

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

2 x^{2} - 13 x - 7

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

(x + 1)^{2}