## K.Binks one year ago What is the foci of a graphed ellipse?

1. K.Binks

2. anonymous

Form this ellipse into the general equation. $\frac{ x^2 }{ a^2 } + \frac{ y^2 }{ b^2 } = 1$

3. anonymous

The ellipse isn't at origin so you need to adjust a little, and use the foci formula $c^2=a^2-b^2$ c = foci

4. K.Binks

Ok, so..is the general equation x^2/-1 + y^2/16= 1?and then use those a and b in the new formula?

5. anonymous

The general equation for this ellipse looks like this $\frac{ (x-2)^2 }{ 3^2 } +\frac{ (y-2)^2 }{ 2^2 } = 1$

6. anonymous

$c^2=3^2-2^2$

7. K.Binks

5? That isn't one of my options.. I'm sorry I'm not understanding this. My options are A) (2 - sqrt5 , 1) and (2 + sqrt5 , 1) B) (2 - sqrt5 , 2) and (2 + sqrt5, 2) C) (2, 1) and (-2, 1) D) (-3, 1) and (3, 1)

8. anonymous

Its square root 5

9. anonymous

you need to get your vertex first

10. anonymous