What is the directrix y=(x-4)(x-2) ?

The directrix y=(x-4)(x-2) is y=-5/4

English

Español

Português

Français

Deutsch

Italiano

Русский

中文(简体)

한국어

日本語

Tiếng Việt

עברית

العربية

Popular >

directrix y=(x-4)(x-2)

directrix

y = (x - 4) (x - 2)

y = - \frac{5}{4}

Solution steps

Rewrite

y = (x - 4) (x - 2)

in the standard form

4 \cdot \frac{1}{4} (y - (- 1)) = (x - 3)^{2}

(h, k) = (3, - 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

(3, - 1)

y-coordinate

y = - 1 - p

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

Refine

y = - \frac{5}{4}

(x - 4)^{2} - 2 (y + 8) = 0

+ \frac{2 h ^{3} + 4 h ^{2} + 5 h}{h}

x^{2} + 6 x - 8

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

y = 18 x^{2} - 6 x + 4