The feasible region for an LPP is shown in the Fig. 12.13. Let F = 3x – 4y be the objective function. Maximum value of F is.

F = 3x – 4y

Corner points are (0, 0), (0, 4), (12, 6)

Value of F at corner points –

At (0, 0), F = 0

At (0, 4), F = -16

At (12, 6), F = 12

Clearly, maximum value of F = 12.