Concept:Constraints are inequalities derived from limited machine hours.Explanation:For machine M1: each chair takes 3 hours, each table takes 3 hours, total available 36 hours, so 3x+3y≤36 which simplifies to x+y≤12.For machine M2: each chair takes 5 hours, each table takes 2 hours, total available 50 hours, so 5x+2y≤50.Also x≥0 and y≥0 because quantities cannot be negative.Answer:x+y≤12, 5x+2y≤50, x≥0, y≥0This matches option B.