All flashcards
Flashcard 1: What is the correct interpretation of a corner point (vertex) of a feasible region in linear constraints?
Answer: An intersection point of boundary lines that is often a candidate optimum. Corner points are where constraint boundaries intersect.
Flashcard 2: What does a constraint mean in a modeling problem?
Answer: A condition that limits allowable values of variables. Constraints establish boundaries for what's mathematically and practically possible.
Flashcard 3: What does it mean for a solution to be viable in a constraints model?
Answer: It satisfies all constraints and matches the real-world context. A viable solution meets all mathematical and practical requirements.
Flashcard 4: What does it mean for a solution to be nonviable in a constraints model?
Answer: It violates at least one constraint or is unrealistic in context. Nonviable solutions fail either mathematical or practical tests.
Flashcard 5: What is a concise way to state the solution set of a system of inequalities in context?
Answer: The set of all viable (x,y) satisfying every constraint. The solution set includes all points meeting every constraint.
Flashcard 6: Identify the constraint for “The total weight is at most 100 lb” if each x weighs 8 lb and each y weighs 5 lb.
Answer: 8x+5y≤100. Weight constraint limits total mass within capacity.
Flashcard 7: What is the correct interpretation of a corner point (vertex) of a feasible region in linear constraints?
Answer: An intersection point of boundary lines that is often a candidate optimum. Corner points are where constraint boundaries intersect.
Flashcard 8: Identify the system for a diet: at least 20 g fiber (2x+5y≥20) and at most 400 calories (50x+80y≤400).
Answer: 2x+5y≥20 and 50x+80y≤400. Multiple constraints model complex nutritional requirements simultaneously.
Flashcard 9: What inequality models “Cost C must not exceed \500$”?
Answer: C≤500. Cost constraints ensure spending stays within budget.
Flashcard 10: What inequality models “Revenue R must be at least \500$”?
Answer: R≥500. Revenue constraints ensure minimum income requirements.
Flashcard 11: Convert the compound inequality 18≤s≤30 into two inequalities.
Answer: s≥18 and s≤30. Compound inequalities split into separate minimum and maximum constraints.
Flashcard 12: Identify the constraint for “At least 10 total items” when the quantities are x and y.
Answer: x+y≥10. Combined quantities must meet or exceed the minimum total.
Flashcard 13: Identify the constraint for “No more than 10 total items” when the quantities are x and y.
Answer: x+y≤10. Combined quantities cannot exceed the maximum total.
Flashcard 14: What does the intersection of the graphs of two inequalities represent?
Answer: The set of points satisfying both inequalities simultaneously. The intersection shows points satisfying multiple constraints simultaneously.
Flashcard 15: Identify the inequality for “y is at least twice x” using variables x and y.
Answer: y≥2x. At least twice means greater than or equal to 2x.
Flashcard 16: Identify the inequality for “y is no more than twice x” using variables x and y.
Answer: y≤2x. No more than twice means less than or equal to 2x.
Flashcard 17: Identify the inequality for “The difference between x and y is at most 5” (single inequality form).
Answer: ∣x−y∣≤5. Absolute value constraints capture differences in either direction.
Flashcard 18: Rewrite the constraint ∣x−y∣≤5 as a system without absolute value.
Answer: x−y≤5 and x−y≥−5. Absolute value inequalities split into two linear constraints.
Flashcard 19: What does it mean if a system of constraints has no solution in context?
Answer: The constraints are inconsistent; there are no viable options. Conflicting constraints create an empty feasible region.
Flashcard 20: What does it mean if a system of constraints has infinitely many solutions in context?
Answer: There are many viable options; the feasible region has area/length. Multiple solutions form a region rather than discrete points.
Flashcard 21: Identify the constraint for “At least 4 units of x” when x must be an integer count.
Answer: x≥4 and x∈Z. Integer constraints model discrete counting situations.
Flashcard 22: What is the meaning of a point outside the feasible region in a modeling context?
Answer: A nonviable option because it breaks one or more constraints. Points outside violate constraints and are impractical solutions.
Flashcard 23: What additional constraint models that x and y count items and cannot be fractional?
Answer: x∈Z and y∈Z (often with x,y≥0). Discrete quantities require integer domain restrictions.
Flashcard 24: A class requires at least 18 students and at most 30. What compound inequality models this for s?
Answer: 18≤s≤30. Compound inequalities capture both minimum and maximum bounds.
Flashcard 25: Which check determines whether (x,y) is a solution to a system of inequalities?
Answer: Substitute into every inequality and verify all are true. A solution must satisfy every constraint in the system.
Flashcard 26: Find whether (4,5) satisfies 2x+y<13.
Answer: Nonviable; 2(4)+5=13 is not less than 13. Strict inequality requires the value be less than, not equal to 13.
Flashcard 27: Find whether (3,2) satisfies the system x≥0, y≥0, and x+y≤4.
Answer: Nonviable; 3+2=5 violates x+y≤4. The sum 3+2=5 exceeds the maximum allowed total of 4.
Flashcard 28: Find whether (1,3) satisfies the system x≥0, y≥0, and x+y≤4.
Answer: Viable; 1+3=4 and both are nonnegative. All constraints are satisfied: 1≥0, 3≥0, and 4≤4.
Flashcard 29: What is the meaning of the boundary line being included in the solution set?
Answer: The inequality uses ≤ or ≥, so equality is allowed. Non-strict inequalities include the boundary as valid solutions.
Flashcard 30: What inequality symbol models “at least” in a constraint statement?
Answer: ≥. Greater than or equal to includes the minimum value.