Help asap.

Nickolas, this is way over your head :)

Dah, a circle is actually a special case of an ellipse.

A circle is an ellipse where for foci are the same point.

This shoud be helpful I think

https://www.youtube.com/watch?v=llJuk41PNIg

If the first foci is $(3,7)$ and the second is $(d, 7)$, then $C =$ $(\frac{d+3}{2}, 7)$. $C$ is the center of the ellipse. The point where the ellipse touches the x-axis is $(\frac{d+3}{2}, 0)$.

We know that $P$(any points on the ellipse) = $T$, so

$2 \sqrt{\left( \frac{d - 3}{2} \right)^2 + 7^2} = d + 3$  

$\sqrt{\left( \frac{d - 3}{2} \right)^2(4) + 7^2(4)} = d + 3$

$\sqrt{(d - 3)^2 + 196} = d + 3$

Then, by squaring both sides, we get 

$(d - 3)^2 + 196 = d^2 + 6d + 9$

$d^2-6d+9+196=d^2+6d+9$

$12d=196$

$d=\frac{49}{3}$

- Daisy