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Linear Equation Solver
Solve ax + b = 0 with full edge cases.
Best for: Use it to solve for an unknown in algebra, physics or everyday word problems.
Input
How it's calculated & sources
The Linear Equation Solver uses the standard, deterministic formula, so the same inputs always produce the same result. It runs entirely in your browser, so your inputs are never uploaded. Last reviewed June 2026.
Free & no sign-up · runs entirely in your browser. Results are estimates for general information, not professional advice — verify important decisions with a qualified expert. Last reviewed June 2026.
How it works
For ax + b = 0, x = −b / a (a ≠ 0).
Example
2x + 6 = 0 → x = −3
Frequently asked questions
What if a = 0?+
If a = 0 and b = 0 the equation is true for all x. If a = 0 and b ≠ 0 there is no solution.
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