What is the directrix y^2=4ax ?

English

Español

Português

Français

Deutsch

Italiano

Русский

中文(简体)

한국어

日本語

Tiếng Việt

עברית

العربية

Popular >

directrix y^2=4ax

directrix

y^{2} = 4 a x

x = - a

Solution steps

Rewrite

y^{2} = 4 a x

in the standard form:

4 a (x - 0) = (y - 0)^{2}

(h, k) = (0, 0), p = a

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

- p

from the center

(0, 0)

x-coordinate

x = 0 - p

x = 0 - a

Refine

x = - a

y^{2} - 2 y - 4 x + 9 = 0

\frac{1}{3} x^{2} - \frac{8}{3} x + \frac{1}{3}

2 x^{2} - 7 x + 15

3 x^{2} - 12 x + 5

18 x^{2} - 6 x + 4