Solving One-Step Equations
An equation has an equals sign — two expressions that are equal. Solving means finding the value of the variable that makes the equation true. The golden rule: whatever you do to one side, do to the other side. Undo the operation to isolate the variable.
Key Concepts
Inverse Operations
Each operation has an opposite: + and −, × and ÷. To solve x + 5 = 12, subtract 5 from both sides: x = 7. To solve 3x = 21, divide both sides by 3: x = 7. Always ask: what operation is being done to x, and what's the inverse?
Checking Your Answer
Always substitute your answer back in: x + 5 = 12, x = 7 → 7 + 5 = 12 ✓. This takes 10 seconds and catches mistakes. Make it a habit.
Equations with Fractions
x/4 = 3 → multiply both sides by 4 → x = 12. x − 3/4 = 1/2 → add 3/4 to both sides → x = 1/4 + 3/4 = 1. Fraction equations look scary but follow the same rules.
🆕 Equation Solver
Enter a one-step equation (like x+5=12 or 3x=21) and see the solution step-by-step.
✅ Check Your Understanding
1. To solve x + 8 = 15, you should...
2. What is the solution to 4x = 28?
3. Why should you check your answer?