Equation Solver
Solve a linear equation ax + b = c, step by step.
What is an equation solver?
An equation solver finds the value of x in a linear equation of the form ax + b = c. It works out the answer step by step, so you can follow the working and check it — ideal for algebra homework.
How to use the equation solver
Enter the values of a, b and c in ax + b = c, then click Solve for x. The solver shows the answer and the steps, including a check that the answer is right.
Formula
For ax + b = c, first subtract b from both sides: ax = c − b. Then divide by a: x = (c − b) ÷ a.
Example
3x + 5 = 20 → 3x = 20 − 5 = 15 → x = 15 ÷ 3 = 5. Check: 3 × 5 + 5 = 20.
Frequently Asked Questions
What is x in 3x + 5 = 20?
x = 5. Try it on the solver above — set a = 3, b = 5 and c = 20.
How do you solve ax + b = c?
Subtract b from both sides, then divide by a: x = (c − b) ÷ a.
What if a is 0?
If a is 0, there is no x term, so the equation has no single solution for x — the solver shows an error instead.
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