What is the directrix y=-1/8 (x-8)^2+2 ?

The directrix y=-1/8 (x-8)^2+2 is y=4

English

Español

Português

Français

Deutsch

Italiano

Русский

中文(简体)

한국어

日本語

Tiếng Việt

עברית

العربية

Popular >

directrix y=-1/8 (x-8)^2+2

directrix

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

y = 4

Solution steps

Rewrite

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

in the standard form:

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

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

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

(8, 2)

y-coordinate

y = 2 - p

y = 2 - (- 2)

Refine

y = 4

y = - 0.23 x^{2} + 1.87 x + 1.5

3 y^{2} = 24 x

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

y = + (x - 7)^{2}

- 2 x^{2} + 25 x