Undo what's happening to x, keeping both sides equal.
- 1
Spot the operation
In x + 5 = 12, x is being added to 5.
- 2
Do the opposite
Subtract 5 from both sides.
x + 5 − 5 = 12 − 5 → x = 7
- 3
Check
Put your answer back in: 7 + 5 = 12 ✓
Topic 9 · Lessons
🧮 Algebra, Indices & Exponents
Variables, powers, and exponential equations.