Consistent or Inconsistent Matrix Calculator

Analyze augmented matrices using structured row reduction. See ranks, pivots, solutions, and consistency decisions clearly. Build confidence through examples, exports, graphs, and plain guidance.

Calculator Input

Example Data Table

Case System Rank(A) Rank([A|b]) Expected Result
Unique x + y + z = 6, 2x − y + z = 3, x + 2y − z = 3 3 3 Consistent with one exact solution
Infinite x + y + z = 6, 2x + 2y + 2z = 12, x − y = 0 2 2 Consistent with infinitely many solutions
Inconsistent x + y + z = 6, 2x + 2y + 2z = 13, x − y = 0 2 3 Inconsistent with no exact solution

Formula Used

Rank Test

Let A be the coefficient matrix and [A|b] the augmented matrix. A system is consistent when rank(A) = rank([A|b]). It is inconsistent when rank(A) ≠ rank([A|b]).

Solution Count Rule

If rank(A) = rank([A|b]) = n, the system has one unique solution. If rank(A) = rank([A|b]) < n, the system has infinitely many solutions.

Row Reduction Rule

Elementary row operations preserve the solution set. The calculator uses row swaps, row scaling, and row replacement to reach reduced row echelon form.

Determinant Check

For square systems, a nonzero determinant confirms a unique solution. A zero determinant means the matrix may still be consistent, but rank testing is required.

How to Use This Calculator

  1. Select a 2 × 2, 3 × 3, or 4 × 4 system.
  2. Enter each coefficient and the constant term for every equation.
  3. Choose the number of decimal places for displayed values.
  4. Press the calculation button to analyze consistency.
  5. Read the ranks, determinant, reduced matrices, and final decision.
  6. Use the example buttons to test unique, infinite, and inconsistent cases.
  7. Export the result block with the CSV or PDF buttons.

Understanding Matrix Consistency

Why consistency matters

A matrix system is useful only when its equations agree with each other. Consistency tells you whether the augmented matrix preserves the same structural information as the coefficient matrix. This calculator checks that relationship carefully. It shows whether a system has one solution, many solutions, or no exact solution.

What the calculator examines

The main test compares rank(A) with rank([A|b]). These ranks are found through row reduction. The calculator also computes the determinant for the square coefficient matrix. That extra value helps interpret singular and nonsingular systems. Every step is displayed so the logic remains transparent.

How row operations help

Row swaps, row scaling, and row replacement simplify the matrix without changing the solution set. Reduced row echelon form exposes pivots and free variables. If every variable column has a pivot, the solution is unique. If at least one variable is free and the ranks still match, the system stays consistent but produces infinitely many valid answers.

How inconsistency appears

An inconsistent system creates a contradictory row after elimination. That row often looks like 0x + 0y + 0z = c, where c is not zero. This means the original equations cannot all be true at the same time. The augmented rank becomes larger than the coefficient rank, and the calculator marks the system as inconsistent.

When to use this tool

Use it for algebra practice, linear systems homework, engineering models, and data setup checks. The example table helps you compare common cases quickly. The export options help save results for reports or revision notes. The graph gives a fast visual comparison between the variable count and both ranks.

FAQs

1. What makes a matrix system consistent?

A system is consistent when the coefficient rank equals the augmented rank. Then at least one exact solution exists. The solution may be unique or infinite.

2. What makes a matrix system inconsistent?

An inconsistent system appears when rank([A|b]) becomes larger than rank(A). This means the equations contradict each other after row reduction.

3. Why does the calculator show determinant values?

The determinant is a quick square-matrix check. A nonzero value guarantees one unique solution. A zero value means you still need the rank test.

4. Can a zero determinant still give a consistent system?

Yes. A zero determinant only means the coefficient matrix is singular. The system can still be consistent with infinitely many solutions if both ranks match.

5. Why are row reduction steps helpful?

The steps show how the original augmented matrix becomes simpler. They reveal pivots, free variables, and contradictions. This makes the final decision easier to trust.

6. Does this tool solve only square systems?

This single-file version focuses on 2 × 2, 3 × 3, and 4 × 4 square systems. That keeps the interface simple and the explanations clear.

7. What is shown for infinite-solution systems?

The calculator labels the system as consistent with infinitely many solutions. It also shows one valid sample solution produced by setting free variables to zero.

8. What does the Plotly graph represent?

The graph compares the number of variables with rank(A) and rank([A|b]). That quick visual helps explain why the system is unique, infinite, or inconsistent.