{{{x,y,z=var('x,y,z') A=matrix(QQ,2,3,1],[4,7,5],[0,-2,2) print A print b = vector([8,20,0]) C = A.augment(b.transpose()) print C print C.swap_rows(1,0) print C print C.add_multiple_of_row(1, 0,-1/2) #C.add_multiple_of_row(1, 2, -2)

print C print

#C.add_multiple_of_row(0, 2, -3) C.add_multiple_of_row(2, 1, -4)

print C print z = C[2,3]/C[2,2] y = (C[1,3]-C[1,2]*z)/C[1,1] x=(C[0,3]-C[0,2]*z-C[0,1]*y)/C[0,0] print "x=",x,"y=",y,"z=",z }}}