Algebra Calculator

Linear Equation Solver

Solve a one-variable linear equation in the form ax + b = 0 and verify the solution by substitution.

Instant answer Formula breakdown Browser-based Mobile friendly

Interactive calculator

Enter your values

Use the example values or replace them with your own. Required validation happens before the calculation.

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Calculated answer

Simple workflow

Follow these steps to get a reliable result and understand how it was produced.

Enter a and b for ax + b = 0.

The constant is isolated from the x term.

Divide by a and verify the resulting x.

Move the constant term to the other side and divide by the non-zero coefficient of x.

x = −b/a

The result panel substitutes your numbers into this relationship and shows the important intermediate values.

If a is zero, the equation is not a one-variable linear equation with one solution.
Negative and decimal coefficients are accepted.
The verification residual should be zero apart from tiny rounding effects.

Helpful answers

Important details about formulas, inputs, limitations, and result interpretation.

The equation no longer determines a unique x in this form.

Yes. Decimal and fractional-equivalent answers are common.

The calculated x is substituted back into ax+b to check that it equals zero.

First rearrange the equation into ax+b=0, then enter the resulting coefficients.