key term - Consistent System

Definition

A consistent system of linear equations is a set of equations that have at least one common solution, meaning the equations are compatible and can be satisfied simultaneously. This concept is central to solving systems of equations using various methods, including substitution, elimination, and applications.

5 Must Know Facts For Your Next Test

1. A consistent system of linear equations has at least one solution that satisfies all the equations simultaneously.
2. The existence of a consistent system is determined by the rank of the coefficient matrix and the rank of the augmented matrix.
3. If the rank of the coefficient matrix is equal to the number of variables, the system is guaranteed to have a unique solution.
4. Consistent systems can be solved using methods like substitution, elimination, or matrix methods, depending on the specific characteristics of the system.
5. Consistent systems are essential in applications that involve optimizing resource allocation, modeling real-world phenomena, and making decisions based on multiple constraints.

Review Questions

• Explain the relationship between the rank of the coefficient matrix and the existence of a unique solution in a consistent system of linear equations.
  • In a consistent system of linear equations, the existence of a unique solution is determined by the rank of the coefficient matrix. If the rank of the coefficient matrix is equal to the number of variables, the system is guaranteed to have a unique solution. This is because the equations in the system are linearly independent, meaning they provide unique constraints that can be satisfied simultaneously. When the rank of the coefficient matrix is less than the number of variables, the system may have infinitely many solutions or no solution at all, depending on the rank of the augmented matrix.
• Describe how the method of substitution can be used to solve a consistent system of linear equations.
  • The method of substitution involves isolating a variable in one equation and then substituting its expression into the other equations. This allows you to reduce the number of variables in the system, ultimately leading to a solution that satisfies all the equations. For a consistent system, the substitution process will result in a solution that can be found by back-substituting the values of the variables. The key to using substitution effectively is to choose the variable to isolate in a way that simplifies the remaining equations and leads to a solution efficiently.
• Analyze how the concept of a consistent system of linear equations is applied in solving real-world problems that involve multiple constraints.
  • Consistent systems of linear equations are essential in modeling and solving real-world problems that involve multiple constraints, such as resource allocation, inventory management, and financial planning. In these applications, the equations represent the various constraints or requirements that must be satisfied simultaneously. By identifying a consistent system, you can find a solution that optimizes the desired outcome while meeting all the necessary conditions. The ability to recognize and solve consistent systems is crucial in making informed decisions, allocating resources efficiently, and understanding the relationships between different variables in complex, multi-faceted problems.

Related terms

Inconsistent System:

An inconsistent system of linear equations is a set of equations that have no common solution, meaning the equations are incompatible and cannot be satisfied simultaneously.

Dependent Equations: Dependent equations in a system are equations that can be expressed as a linear combination of the other equations, meaning they provide redundant information and do not add new constraints to the system.

Augmented Matrix: The augmented matrix of a system of linear equations is a matrix that combines the coefficients of the variables and the constants on the right-hand side of the equations, allowing for efficient analysis and manipulation of the system.