Calculator
Formula used
A linear system can be written as an augmented matrix. The calculator applies row operations that keep the same solution set. The main elimination rule is:
Ri = Ri - (aik / akk)Rk
Here, Rk is the pivot row. Ri is the row being changed. akk is the pivot value. aik is the value below or above the pivot.
The process continues until each pivot column is reduced. For a unique answer, the final matrix gives x, y, and z directly. If coefficient rank and augmented rank differ, the system has no solution. If rank is smaller than the number of variables, the system has infinitely many solutions.
How to use this calculator
- Select a two variable or three variable system.
- Enter each coefficient beside the matching variable.
- Enter the right side constant for each equation.
- Set decimal places and zero tolerance when needed.
- Press the solve button.
- Review the result above the form.
- Use the CSV or PDF buttons to save the work.
Example data table
| Example | Equation 1 | Equation 2 | Equation 3 | Expected result |
|---|---|---|---|---|
| Two variable | 2x + 3y = 13 | 5x - 2y = 4 | Not used | x = 2, y = 3 |
| Three variable | 2x + 3y - z = 5 | 4x - y + 2z = 6 | -2x + 5y + 3z = 7 | Unique solution |
| No solution | x + y = 3 | 2x + 2y = 8 | Not used | Inconsistent system |
Understanding Elimination
Elimination is a direct way to solve linked linear equations. It removes one variable at a time. The goal is to create simpler equations that still describe the same system. Each row operation keeps the solution unchanged. This makes the method dependable for homework, tutoring, and quick checking.
Why This Calculator Helps
Manual elimination can become messy when coefficients are large. Fractions also create mistakes. This calculator organizes the coefficients, chooses pivots, and records every row operation. It can solve two variable and three variable systems. It also reports when a system has no unique answer. That includes inconsistent systems and dependent systems.
Working With Equations
A linear system uses equations such as ax plus by equals c. A three variable system adds z terms. The calculator reads each coefficient as a number. Then it builds an augmented matrix. The last column stores the right side constants. The matrix form keeps all equations compact and easier to compare.
Checking the Result
A correct solution should satisfy every original equation. Substitute each returned value into the starting system. The left side should match the right side within the selected tolerance. Small decimal differences can occur after rounding. Use more decimal places when you need a finer answer.
Practical Uses
Students can use the tool to learn row operations. Teachers can prepare examples for lessons. Engineers and planners can test small linear models. Business users can balance simple constraints. The export buttons also help save work for notes, reports, or class records.
Best Practices
Enter every missing coefficient as zero. Use negative signs where terms are subtracted. Keep units consistent if the variables represent real quantities. Start with two equations when learning the process. Move to three equations after the steps feel familiar. Review the pivot steps before trusting the final answer. This builds skill, not just speed.
Common Input Mistakes
Many errors come from misplaced constants. Put only the answer number in the right side box. Do not enter equal signs. Decimal coefficients are allowed. Fractions should be converted to decimals first. If a pivot is almost zero, raise the tolerance only when the data is noisy. Lower it for exact classroom values. This avoids false warnings during solving.
FAQs
What does elimination mean?
Elimination means removing one variable from an equation pair or group. It uses addition, subtraction, scaling, and row operations while keeping the same solution.
Can this calculator solve three variable systems?
Yes. Select the three equation option. Then enter x, y, z, and right side values for all three equations.
What is a pivot?
A pivot is the main value used to clear other values in the same column. Good pivots make elimination stable and easier to follow.
Why does it say no solution?
No solution means the equations conflict. During elimination, the calculator found that the coefficient rank and augmented rank do not match.
Why does it say infinitely many solutions?
This means the equations are dependent. There are fewer independent equations than variables, so more than one solution can satisfy the system.
Should blank coefficients be entered as zero?
Yes. If a variable is missing from an equation, enter zero for that coefficient. This keeps the matrix structure correct.
Can I download the result?
Yes. After solving, use the CSV button for spreadsheet data. Use the PDF button for a simple report with steps.
Does this solve nonlinear systems?
No. This calculator is for linear equations only. It does not solve equations with powers, products of variables, or curves.