Equation of the ellipse with vertices (±5,0) foci (±4,0) is
Vertices,A = (±5,0), a = 5
Foci,S = (±4,0), ae = 4 ⇒e = 45
Centre,C = (0,0), b2 = 25(1−1625) = 9
x225+y29 = 1