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

The directrix y=x^2-4x-3 is y=-29/4

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directrix y=x^2-4x-3

directrix

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

y = - \frac{29}{4}

Solution steps

Rewrite

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

in the standard form

4 \cdot \frac{1}{4} (y - (- 7)) = (x - 2)^{2}

(h, k) = (2, - 7), 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, - 7)

y-coordinate

y = - 7 - p

y = - 7 - \frac{1}{4}

Refine

y = - \frac{29}{4}

y = - x^{2} + 6 x

y = x^{2} - 4 x + 5

- 2 x^{2} - 3 x - 1

y = x^{2} - 6 x - 12

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