(1)  Notice that the center and the vertex (and the focus) all lie on horizontal line y = -2.


     It means that the major axis is horizontal, and the major semi-axis is horizontal, too.

     
(2)  The length of the major semi-axis  " a "  is the distance between the vertex and the center, 
     i.e. equals 7-2 = 5 units:  a = 5.


(3)  The focal distance (between the center and the focus) is  4-2 = 2 units:  c = 2.


     Hence, for the minor semi-axis  "b"  we have  b =  = .


(4) Thus the standard form equation of the ellipse is 


          +  = 1,

     or

          +  = 1.      ANSWER