The foci of the given ellipse  = (0 ,-√5 ) and ( 0, √5 )
Step-by-step explanation:
Step(i):-
Given Ellipse  9 x² + 4 y² = 36
          Â
        ⇒  Â
Step(ii):-
 The Major axis lies on y-axis
  Foci of the Formula C² = a² -b² = 9-4 =5
                 C = √5
The Foci is always lie on the major axis(longest) axis, spaced equally each side of the centre
Given ellipse of the foci is lie on Y- axis
Final answer:-
The foci of the given ellipse  = (0 ,-√5 ) and ( 0, √5 )