The major axis of the eclipse is 12 units long
The given parameters can be represented as:


See attachment for illustration
To solve this question, we make use of the following theorem
The distance between a point and the foci sums up to the major axis
This translates to:



The answer should be $13 !! hope that helps
The answer would be 16
11 + (8-3)^2 - 20 = 16