Could you help me to solve the following problem? Let x* be an optimal solution to the problem: min z = ctx s.t. a x = bi, i = 1,2, ..., m x > 0 where the row vector a is the i-th row of the coefficient matrix A. Let y* be an optimal dual solution. Show that x* is also an optimal solution to the problem: min z= (cT yaz)x s.t. ax = b i = 1,2, ...,m, i+ k x > 0 where y is the k-th component of y*