ToolBark
Math

System of Equations Solver

Solve 2x2 and 3x3 linear systems instantly with step-by-step working

System Size

Enter Coefficients

Each row: a·x + b·y = c

a (x coeff)b (y coeff)c (RHS)Eq 1Eq 2

Eq 1: 2x + 3y = 8

Eq 2: 5x - y = 3

Solution

x1
y2
Show Cramer's Rule working

Determinants

D = -17

Dx = -17

Dy = -34

x = Dx / D = -17 / -17 = 1

y = Dy / D = -34 / -17 = 2

Verification

Eq 1LHS = 8    RHS = 8
Eq 2LHS = 3    RHS = 3

How It Works

Cramer's Rule
Solves the system using determinants. x = Dx/D, y = Dy/D (and z = Dz/D for 3×3).
Determinant D = 0
If the coefficient determinant is zero, the system has no unique solution — it's either inconsistent (no solution) or dependent (infinite solutions).
Verification
After solving, the tool substitutes the values back into each equation to confirm correctness.
Precision
Results are rounded to 10 significant figures. Floating-point arithmetic is used; very large coefficients may lose precision.
About

Solve a system of linear equations instantly with this free online calculator. Enter coefficients for a 2×2 or 3×3 system and get exact solutions using Cramer's Rule — complete with determinant working and automatic back-substitution verification. No software to install, no account required. Ideal for students, engineers, and anyone checking algebra homework.

FAQ
What is a system of equations?+

A system of equations is a set of two or more equations that share the same variables. Solving the system means finding values for each variable that satisfy all equations simultaneously.

How does the solver work?+

The tool uses Cramer's Rule, which expresses each variable as a ratio of determinants. For a 2×2 system, x = Dx/D and y = Dy/D, where D is the coefficient matrix determinant and Dx, Dy are determinants formed by replacing the respective column with the constants.

What happens if there is no unique solution?+

When the main determinant D equals zero, the system either has no solution (inconsistent — the lines or planes are parallel) or infinitely many solutions (dependent — the equations describe the same line or plane). The solver detects and reports both cases.

How accurate are the results?+

Results are calculated using IEEE 754 double-precision floating-point arithmetic and rounded to 10 significant figures. The solver also substitutes the answers back into each original equation so you can confirm correctness directly on screen.

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