Equations · Linear algebra

Linear Systems 2×2 & 3×3 Calculator

Solve two- or three-variable linear systems with Gaussian elimination and classify each system as unique, inconsistent, or dependent.

Formula shown Runs locally Reviewed Aug 11, 2026
Follow us on Google
Equation guide

Two or three simultaneous linear equations over the real numbers

Matrix form

A𝐱 = 𝐛

Unique solution

rank(A) = rank([A|𝐛]) = n

Other cases

rank(A) < rank([A|𝐛]) → nonerank(A) = rank([A|𝐛]) < n → infinite
Linear algebra

Classify and solve a linear system

Inputs and displayed decimal results use at most three decimal places. Exact internal values are retained during calculation.

A𝐱 = 𝐛

Enter the coefficient matrix and the constants column.

Using the model

Symbols, assumptions and limitations

Interpretation notes

The calculator uses real coefficients and Gaussian elimination with partial pivot selection. A unique solution requires full coefficient rank. A contradictory reduced row means no solution, while fewer pivots than variables without contradiction means infinitely many solutions.

Worked examples

See the method in practice

01

Unique 2×2 system

x + y = 4 and x − y = 2 reduce to x = 3 and y = 1.

02

Inconsistent system

x + y = 2 and 2x + 2y = 5 have proportional left sides but incompatible constants, so no solution exists.

Questions

Frequently asked

What does infinitely many solutions mean?

At least one equation is dependent on the others, leaving one or more free variables.

Why use row operations?

They preserve the solution set while transforming the augmented matrix into a form that exposes pivots and contradictions.

Can decimal coefficients be used?

Yes, with at most three decimal places per input.

Sources & review

Equations and examples are checked against the references below. Results are educational and should be independently verified for safety-critical work.

OpenStax College Algebra — Systems of Linear Equations

Written by the STEM Hub editorial team · Reviewed August 11, 2026 · Review methodology