Question

[Systems of equations] (/20) 1. Suppose the coefficient matrix of a system of linear equations has a pivot position in every row. Explain why the system is consistent.

Answer 1

Answer:

The system is consistent because the rightmost column of the augmented matrix is not a pivot column.

Step-by-step explanation:

It is given that the coefficient of the matrix of a linear equation has a pivot position in every row.

It is provided by the Existence and Uniqueness theorem that linear system is said to be consistent when only  the column in the rightmost of the matrix which is augmented is not a pivot column.

When the linear system is considered consistent, then every solution set consists of either unique solution where there will be no any variables which are free or infinitely many solutions, when there is at least one free variable. This explains why the system is consistent.

For any m x n augmented matrix of any system, if its co-efficient matrix has a pivot position in every row, then there will never be a row of the form [0 .... 0 b].