CIRCLES ..//


@YouKnowwhere Add both equations,the circle will pass through all intersection points.

@YouKnowwhere for writing the family of cureves through the point of intersection of given ellipse and hyperbola ..the family of given curves will be
S1+lamdaS2=0......now we want a circle so make the coefficients of x^2 and y^2 equal ....which on solving will give the value of lamda which will come out to be 1 ...so the equation of circle passing through point of intersection will be S1+S2=0...so add the eqn of given two curves directly