The locus of the centres of the circles which cut the circles x2+y2+4x-6y+9=0 and x2+y2-5x+4y-2=0 orthogonally is

Given circles are S1:x2+y2+4x-6y+9=0 and S2:x2+y2-5x+4y-2=0∴ locus of centres is S1-S2=0⇒9 x-10 y+11=0This is radical axis, difference of equations of two circles