If mr,1mr;r=1,2,3,4 are four pairs of values of x and y that satisfy the equation x2+y2+2gx+2fy+c=0, then value of m1⋅m2⋅m3⋅m4

mr,1mr satisfy the given equation x2+y2+2gx+2fy+c=0 then mr2+1mr2+2gmr+2fmr+c=0⇒ mr4+2gmr3+cmr2+2fmr+1=0 Now roots of given equation are m1,m2,m3,m4 Product of roots =m1m2m3m4= constant term  coefficeint of mr4=11=1