The general equation for an ellipse with horizontal major axis is `y = (x - h)^2/a^2 + (y-k)^2/b^2`

The value of a = 11 as that is the distance from the center (-7, 6) to a vertex. The value of b is 9 as that is the distance to a co-vertex...

## See

This Answer NowStart your **48-hour free trial** to unlock this answer and thousands more. Enjoy eNotes ad-free and cancel anytime.

Already a member? Log in here.

The general equation for an ellipse with horizontal major axis is `y = (x - h)^2/a^2 + (y-k)^2/b^2`

The value of a = 11 as that is the distance from the center (-7, 6) to a vertex. The value of b is 9 as that is the distance to a co-vertex since the center.

This means that `a^2 = 11^2 = 121` and `b^2 = 9^2 = 81.`

Therefore, the denominators are 121 and 81, respectively.

The distance from C to foci can be found by `F =sqrt(a^2 - b^2).`

"a" represents the semi-major axis and "b" represents the semi-minor axis.

`F =sqrt(11^2 - 9^2)`

`F =sqrt(121-81)`

`F =sqrt(40)` = `2sqrt(10)` ≈ `6.325`

**The solutions are, the first denominator is 121, the second denominator is 81, and the distance c=from C to foci is `2sqrt(10)` or 6.325.**

` `