Linear Equation Step Checker: Verify Algebra
Paste your original linear equation and each new step on a separate line. The checker compares the solution set of each line with the preceding line. It flags steps that change the set; it does not claim to understand or grade your reasoning.
Worked example: the algebra appears right, but a step is wrong
Take 3(2x - 1) = 15. Distribute carefully: 6x - 3 = 15, then 6x = 18 and finally x = 3. All four lines represent the same one-value solution set. Now change the second line to 6x - 1 = 15. The tool flags that transition because the new equation has the different solution x = 8/3. That does not prove precisely which rule you tried; it tells you to revisit the work.
Open our guide to checking AI-assisted mathematics for input transcription, answer substitution and word-problem restrictions.
Why checking solution sets is not the same as proving a step
Two equations can share their complete solution set even if the written transition has no clear pedagogical justification. This tool compares the solutions exactly using rational-number algebra; it does not judge whether you wrote a named operation correctly. Multiplying both sides of x = 4 by zero would give 0 = 0, which has every real number as a solution and is therefore flagged. Likewise, changing a fraction to a rounded decimal such as x = 0.33333333 when the original demands x = 1/3 will be detected as non-equivalent.
OpenStax's college algebra methodology demonstrates how to simplify, collect terms and substitute the answer back into the original equation. Always do this last check; our tool does not translate a story problem into mathematics or verify units and physical restrictions.