Simple Equations
Year 7 📊 Algebra Solve one-step and two-step linear equations.
⚖️ What is an Equation?
An equation states that two expressions are equal. Solving means finding the value of the unknown.
Think of an equation as a balance scale. Whatever you do to one side, you must do to the other to keep it balanced.
🔧 Solving One-Step Equations
Use inverse operations to isolate the variable.
- Identify what operation is applied to the variable.
- Apply the inverse operation to both sides.
Example: Solve $x + 7 = 15$ → subtract 7 from both sides → $x = 8$
Example: Solve $4x = 28$ → divide both sides by 4 → $x = 7$
📐 Solving Two-Step Equations
When two operations are applied, undo them in reverse BODMAS order.
- Add or subtract first (undo the + or -).
- Then multiply or divide (undo the times or divide).
Example: Solve $3x - 5 = 16$ → add 5: $3x = 21$ → divide by 3: $x = 7$
Example: Solve $\frac{x}{4} + 2 = 6$ → subtract 2: $\frac{x}{4} = 4$ → multiply by 4: $x = 16$
Ready to test yourself? Click the Quiz tab above to answer questions on this topic!
Interactive Demonstration — Simple Equations
Solving: ax + b = c
⚖️ Equation Solver
Type 1: ax + b = c
Type 2: ax + b = cx + d