The simplest equations—one operation, one step. Master these and you're ready for anything.
Need help now? Paste your equation into our ai math solver for instant step-by-step solutions.
Solve Now →A one-step equation needs just one operation to solve. The variable is being added to, subtracted from, multiplied by, or divided by a number—and you undo that with the inverse (opposite) operation.
Addition ↔ Subtraction
x + 5 = 12 → subtract 5
x - 3 = 7 → add 3
Multiplication ↔ Division
4x = 20 → divide by 4
x/6 = 3 → multiply by 6
For more foundational practice, check out Purplemath's equation guide.
Example: x + 7 = 15
Example: x - 4 = 9
Example: 5x = 35
Example: x/3 = 8
Example: -2x = 14
| If you see... | Do this... | Example |
|---|---|---|
| x + a = b | Subtract a from both sides | x + 5 = 12 → x = 7 |
| x - a = b | Add a to both sides | x - 3 = 10 → x = 13 |
| ax = b | Divide both sides by a | 6x = 42 → x = 7 |
| x/a = b | Multiply both sides by a | x/4 = 5 → x = 20 |
Using the wrong inverse
If x is being multiplied, you divide (not subtract). Match the operation!
Sign errors with negatives
Dividing by a negative number flips the sign: -3x = 15 means x = -5, not 5.
Not checking the answer
Always plug your answer back in. It takes 5 seconds and catches most mistakes.
Try these on your own, then check:
Answers:
Type any equation and get instant step-by-step solutions.
Try AI Math Solver →