Question

Find the constant sum for an ellipse with foci F1 (2, 0), F2 (-6, 0) and the point on the ellipse (2, 6).

Answer 1

I know the formula but I keep getting different answers
I first got 216
Then I got 136

Answer 2

\(\bf \textit{distance between 2 points}\\ \quad \\
\begin{array}{lllll}
&x_1&y_1&x_2&y_2\\
F1&({\color{red}{ 2}}\quad ,&{\color{blue}{ 0}})\quad &({\color{red}{ 2}}\quad ,&{\color{blue}{ 6}})\\
F2&({\color{red}{ -6}}\quad ,&{\color{blue}{ 0}})\quad &({\color{red}{ 2}}\quad ,&{\color{blue}{ 6}})
\end{array}\qquad
d = \sqrt{({\color{red}{ x_2}}-{\color{red}{ x_1}})^2 + ({\color{blue}{ y_2}}-{\color{blue}{ y_1}})^2}
\)
sum both distances