WILL GIVEBRAINLIEST AND 25 PTS PLEASE HURRY!!!Which lines are the directrices of the ellipse?
x = −4.25 and x = 8.25
x = −3.25 and x = 9.25
y = −4.25 and y = 8.25
y = −3.25 and y = 9.25

WILL GIVEBRAINLIEST AND 25 PTS PLEASE HURRYWhich lines are the directrices of the ellipse x 425 and x 825 x 325 and x 925 y 425 and y 825 y 325 and y 925 class=

Respuesta :

Answer:

The directrix of the ellipse is:

x= -3.25 and x=9.25

Step-by-step explanation:

As we know that for any ellipse equation of the type:

[tex]\dfrac{(x-h)^2}{a^2}+\dfrac{(y-k)^2}{b^2}=1[/tex] and a>b

The directrix is given by:

[tex]x=h\pm \dfrac{a}{e}[/tex]

where,

[tex]e=\sqrt{1-\dfrac{b^2}{a^2}}[/tex]

Here we have the equation of parabola as:

[tex]\dfrac{(x-3)^2}{5^2}+\dfrac{(y-2)^2}{3^2}}=1[/tex]

Hence, we have:

[tex]h=3,\ k=2,\ a=5,\ b=3\\\\and\\\\e=\sqrt{1-\dfrac{3^2}{5^2}}\\\\e=\sqrt{1-\dfrac{9}{25}}\\\\e=\sqrt{\dfrac{25-9}{25}}\\\\\\e=\sqrt{\dfrac{16}{25}}\\\\e=\dfrac{4}{5}[/tex]

Hence, we have: the directrix as:

[tex]x=3\pm \dfrac{5}{\dfrac{4}{5}}\\\\\\x=3\pm \dfrac{25}{4}\\\\Hence, x=9.25\ and\ x=-3.25[/tex]

Hence, the equation of directrix is:

x= -3.25 and x=9.25

Answer:

B

Step-by-step explanation:

On edge