Respuesta :

Your ellipse has center (h, k) = (0, 0) and x- and y- semi-axis lengths of a=2 and b=12, respectively. The equation is
  (x-h)²/a² + (y-k)²/b² = 1

For your values, the equation is
  x²/4 + y²/144 = 1
Ver imagen sqdancefan