Matrix d using coeff as given in cramer 's rule
double [ , ] d = { { coeff [ 0 , 0 ] , coeff [ 0 , 1 ] , coeff [ 0 , 2 ] } , { coeff [ 1 , 0 ] , coeff [ 1 , 1 ] , coeff [ 1 , 2 ] } , { coeff [ 2 , 0 ] , coeff [ 2 , 1 ] , coeff [ 2 , 2 ] } , } ;