Linear Equation Solver
ax + b = 0 → x = −b / a. Single-variable linear equations in standard form.
Result
x
4.000000
3x + -12 = 0.
- Equation3x + -12 = 0
- a3
- b-12
- x4.00000000
- Verification3 × 4.0000 + -12 = 0.0000
Step-by-step
- 3x + -12 = 0
- → 3x = −-12
- → x = −-12 / 3 = 4.00000000.
How to use this calculator
- Enter a and b.
- Read x.
About this calculator
A linear equation in one variable has the form ax + b = 0; solution x = −b/a (provided a ≠ 0). When a = 0, the equation degenerates: if b = 0, every real number is a solution; if b ≠ 0, no solution. Linear equations are the foundation of algebra — every other equation type extends or specializes them. Used in conversions, simple physics (constant velocity), and as a step inside more complex solves (e.g. Gaussian elimination).
Frequently asked
If a = 0, equation isn't actually linear — it's either always true or never true.
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