Step 1: In a Linear Programming Problem (LPP), if the objective function \( Z = ax + by \) has the same value at two corner points of the feasible region, then the maximum value of \( Z \) will occur at all points on the line segment joining these two corner points.
Step 2: Since the line segment contains infinitely many points, the number of points at which \( Z \) attains its maximum value is infinite.
The system of simultaneous linear equations :
\[ \begin{array}{rcl} x - 2y + 3z &=& 4 \\ 2x + 3y + z &=& 6 \\ 3x + y - 2z &=& 7 \end{array} \]