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Any equation, solved with every step named as your teacher would name it.
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The Coddy math course teaches the method itself - you work each step on an interactive board and get told exactly where a move went wrong.
Every equation you will meet in school algebra is solved the same way: you do the same thing to both sides, over and over, until the letter stands alone. What changes from problem to problem is which move to make next, and that is the only thing worth learning. An answer alone teaches you none of it.
So this solver shows the moves. Each line says what was done - "Subtract 7 from both sides", "Split into cases", "Cross multiply" - and then shows the equation that move produced. The names are not invented for this page: they are the same names the Coddy math course uses on its interactive board, because the calculator and the course run on one engine.
It also chooses the route the way a teacher would rather than the way a computer would. Factoring beats the quadratic formula where factoring applies, because it is shorter and it is what you would do by hand. The number of steps shown is the number of steps the problem actually takes.
Write it the way you would on paper: 2x + 3 = 11, x^2 - 5x + 6 = 0, (x+1)/(x-2) = 3. Use ^ for powers, sqrt(...) for roots and |x| for absolute value.
With more than one letter in the equation a row of buttons appears. That is how you rearrange a formula: put in A = l w and pick l to get l = A/w.
The answer sits at the top because that is what most people came for. The numbered steps below it are the part worth reading twice.
If you got a different answer, the useful question is not which number is right but which line diverged. Find that line and the mistake usually explains itself.
One solver, and it picks the method rather than asking you to. These are the shapes it recognises and the first move it makes on each.
| Kind of equation | Example | How it starts |
|---|---|---|
| Linear | 3x + 7 = 22 | Move the constant, then divide |
| Unknown on both sides | 5x - 4 = 3x + 6 | Collect the x terms on one side first |
| Brackets | 2(x - 3) = 4x + 1 | Divide through or expand, whichever is shorter |
| Quadratic | x² - 5x + 6 = 0 | Factor if it factors, otherwise the quadratic formula |
| Fractions and rationals | (x+1)/(x-2) = 3 | Cross multiply, then solve what is left |
| Absolute value | |x - 1| = 4 | Split into the two cases the bars stand for |
| Radical | √(x + 3) = 5 | Square both sides, then check for extraneous roots |
| Systems | 2x + y = 5; x - y = 1 | Eliminate one unknown, then substitute back |
| Inequalities | 3x + 2 > 11 | The same moves, with the sign flipping on a negative divide |
| Formulas (literal) | A = l w | Pick the letter you want and isolate it |
3x + 7 = 22Two moves. The 7 goes to the other side, leaving 3x = 15, and then dividing by 3 gives x = 5. Notice the solver does not 'subtract 7 from both sides' and then 'divide both sides by 3' as separate ceremonies - it names each move by what it accomplishes, which is how you would describe it out loud.
5x - 4 = 3x + 6The first job is to get every x onto one side. After that it is the previous example again. This is the shape that first convinces students that algebra is a procedure rather than a puzzle, and it is worth doing a dozen of them until the first move is automatic.
x^2 - 5x + 6 = 0Factoring gives (x - 3)(x - 2) = 0, and then the zero-product rule splits it into two cases, each of them a one-step linear equation. The quadratic formula would also work and would take four more lines - which is exactly why the solver does not use it here.
A = l wPick l in the 'Solve for' row and the solver moves w across, giving l = A/w. This is the same machinery as solving for x, and realising that is one of the more useful moments in a first algebra course: a formula is just an equation whose letters have names.
