Hi
Standard Form of an Equation of an Ellipse is
where Pt(h,k) is the center and a and b are the respective vertices distances from center.
(x-1)^2/25 + (y+2)^2/16 = 1 | a = 5 and b = 4 C(1,-2)
f = sqrt(25-16) = 3 (foci are located 3 each side of center along major axis)
|foci are (-2,-2) and (4,-2)