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Linear Equation Solver

Solve ax + b = c for x online for free. Our linear equation solver shows every algebraic step — subtracting the constant, dividing by the coefficient, and verifying the answer. Handles unique solutions, no solution (contradiction), and infinitely many solutions (identity). No signup required, all calculations run locally in your browser.

Linear Equation Solver

Enter the coefficients for the equation ax + b = c and click Solve. The solver shows every algebraic step — subtraction, division, and verification. All calculations run locally in your browser.

Equation: ax + b = c
3x +5 = 14
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Why Use Our Linear Equation Solver?

Step-by-Step Algebraic Solution

Our linear equation solver shows every algebraic step — subtracting the constant, dividing by the coefficient, and verifying the answer by substitution. See exactly how ax + b = c is solved, not just the final x value.

Handles All Cases — Unique, No Solution, Infinite

Our linear equation solver correctly identifies all three solution types: a unique solution (x = value), no solution (contradiction like 3 = 7), and infinitely many solutions (identity like 5 = 5). Each case is explained clearly.

Secure Linear Equation Solver Online

All equation solving happens locally in your browser — your coefficients never leave your device. Use our linear equation solver online with complete privacy and no data collection of any kind.

Live Equation Preview & Fraction Form

Our linear equation solver shows a live preview of your equation as you type the coefficients. Results include both decimal and exact fraction form, plus a verification step confirming the answer is correct.

Common Use Cases for Linear Equation Solver

Algebra Homework & Education

Solve linear equations step by step for algebra homework, exams, and coursework. Students use our linear equation solver to check their work and understand the algebraic process — not just get the answer.

Physics & Engineering Problems

Solve for unknown variables in physics formulas like F = ma, V = IR, and d = vt rearranged as linear equations. Our linear equation solver handles decimal and fractional coefficients for real-world scientific calculations.

Finance & Business Calculations

Solve break-even equations, profit formulas, and cost-revenue models expressed as linear equations. Use our linear equation solver to find the unknown quantity when all other values are known.

Teaching & Tutoring

Use the step-by-step solution display to teach algebra concepts to students. Our linear equation solver shows each algebraic operation clearly — subtract constant, divide by coefficient, verify — making it ideal for classroom and tutoring use.

Quick Verification

Verify hand-calculated solutions to linear equations instantly. Enter your coefficients and check whether your answer matches — our linear equation solver also shows the verification step so you can confirm the logic.

Programming & Algorithm Testing

Test linear equation solving implementations and verify edge cases (a = 0, infinite solutions, no solution). Our linear equation solver handles all degenerate cases correctly, making it useful for algorithm validation.

Understanding Linear Equations

What is a Linear Equation?

A linear equation in one variable is an equation of the form ax + b = c, where a, b, and c are real numbers and x is the unknown variable. The equation is called "linear" because the variable x appears to the first power only — no x², x³, or other powers. Solving a linear equation means finding the value of x that makes the equation true. Our linear equation solver handles all cases: a unique solution when a ≠ 0, no solution when a = 0 and b ≠ c (a contradiction), and infinitely many solutions when a = 0 and b = c (an identity).

How Our Linear Equation Solver Works

  1. 1. Enter Coefficients: Type the values of a (coefficient of x), b (constant on the left side), and c (right-hand side) in the input fields. The linear equation solver shows a live preview of your equation as you type. All processing happens locally in your browser — your data never leaves your device.
  2. 2. Algebraic Steps Applied: Click "Solve for x" and the linear equation solver applies the standard algebraic procedure: subtract b from both sides to isolate the x term, then divide both sides by a to find x. Each step is shown with a description and the resulting equation.
  3. 3. Verified Result: The linear equation solver substitutes the solution back into the original equation to verify correctness. Results are shown in both decimal and exact fraction form for complete accuracy.

The Three Solution Cases

  • Unique Solution (a ≠ 0): When the coefficient of x is non-zero, the equation has exactly one solution: x = (c − b) / a. For example, 3x + 5 = 14 → x = (14 − 5) / 3 = 3. This is the most common case in our linear equation solver.
  • No Solution (a = 0, b ≠ c): When a = 0, the equation becomes b = c. If b ≠ c, this is a contradiction — a false statement with no solution. For example, 0x + 3 = 7 → 3 = 7, which is impossible. Our linear equation solver identifies this case and explains it clearly.
  • Infinite Solutions (a = 0, b = c): When a = 0 and b = c, the equation becomes b = b — an identity that is always true. Any value of x satisfies the equation, so there are infinitely many solutions. For example, 0x + 5 = 5 → 5 = 5 ✓ for all x.
  • Fraction Form: When the solution is not an integer, our linear equation solver displays it as a simplified fraction (e.g. x = 7/3) in addition to the decimal form (x ≈ 2.333...). The fraction is reduced to lowest terms using the GCD.

Solving ax + b = c — The Standard Method

The standard algebraic method for solving ax + b = c has two steps. First, subtract b from both sides to get ax = c − b. This isolates the x term by removing the constant from the left side. Second, divide both sides by a to get x = (c − b) / a. This isolates x completely. The key principle is that any operation applied to one side of an equation must be applied to the other side to maintain equality. Our linear equation solver shows each of these operations explicitly, making the algebraic reasoning transparent and easy to follow.

Frequently Asked Questions About Linear Equation Solver

A linear equation solver finds the value of x in an equation of the form ax + b = c. Our linear equation solver shows every algebraic step — subtracting the constant, dividing by the coefficient, and verifying the answer — for all three solution cases: unique solution, no solution, and infinitely many solutions.

Step 1: Subtract 5 from both sides → 3x = 9. Step 2: Divide both sides by 3 → x = 3. Verify: 3(3) + 5 = 14 ✓. Enter a=3, b=5, c=14 in our linear equation solver to see this breakdown automatically.

When the coefficient a = 0 and b ≠ c, the equation becomes b = c — a false statement called a contradiction. For example, 0x + 3 = 7 simplifies to 3 = 7, which is impossible. No value of x can satisfy this equation.

When a = 0 and b = c, the equation becomes b = b — an identity that is always true regardless of x. For example, 0x + 5 = 5 simplifies to 5 = 5, which is true for any value of x. Every real number is a solution.

Yes! Our linear equation solver accepts any real number for a, b, and c — including decimals like 0.5 and negative numbers like -3.7. The solution is shown in both decimal and exact fraction form.

The formula is x = (c − b) / a, valid when a ≠ 0. Derived by: (1) subtracting b from both sides to get ax = c − b, then (2) dividing both sides by a to get x = (c − b) / a.

After finding x, our linear equation solver substitutes the value back into the original equation: a(x) + b should equal c. If it does, the solution is confirmed correct. This verification step is shown explicitly in the step-by-step breakdown.

Absolutely. All equation solving happens locally in your browser using JavaScript. Your coefficients are never sent to any server, ensuring complete privacy every time you use our linear equation solver online.

Yes! Our linear equation solver is 100% free with no signup, no usage limits, and no premium features. Solve equations as many times as you need — completely free, forever.