What is the equation of the director circle of the ellipse x225+y29=1\frac{x^2}{25} + \frac{y^2}{9} = 125x2+9y2=1?
x2+y2=34x^2 + y^2 = 34x2+y2=34
x2+y2=16x^2 + y^2 = 16x2+y2=16
x2+y2=25x^2 + y^2 = 25x2+y2=25
x2+y2=9x^2 + y^2 = 9x2+y2=9