The set of constraints 4X+lY<90 Constraint due to Wood 2X+lY<50 Constraint due to Machine-Time] 1X+ lY<40 [Constraint due to Polishing-Timel X20, Y20 [non-negative constraint The set of constraints – 4X + 1Y  90 [Constraint due to Wood] – 2X + 1Y  50 [Constraint due to Machine-Time] – 1X + 1Y  40 [Constraint due to Polishing-Time] – X0, Y  0 [non-negative constraint]