Algebra resources
Mathematics, grade 9. Notes, worksheets, videos, interactive tools and revision materials for this chapter.
Study notes
The chapter's lessons are the notes — read them in order, then use the resources below.
Practice worksheet
Attempt every question before revealing the answer — that struggle is where learning happens.
5x = 20, so x = 4. Check: 5(4) + 3 = 23 ✓
−2x = −6, so x = 3. Check: 7 − 2(3) = 1 ✓
4x − 12 = 2x + 6 → 2x = 18 → x = 9. Check: 4(6) = 24 = 2(9) + 6 ✓
x/4 = 7, so x = 28. Check: 28/4 + 5 = 12 ✓
2(w + w + 3) = 26 → 4w + 6 = 26 → w = 5 cm. Length = 8 cm.
3x − 7 = 2x + 7 → x = 14. Check: 3(14) − 7 = 35 = 2(18) − 1 ✓
Watch and learn
Hand-picked searches to find a clear video explanation of each lesson.
Try it yourself
Type any linear equation and watch it solved step by step — then try the steps yourself.
Press Solve to see each step — then cover the steps and try the next one yourself.
Revision checklist
Can you explain each of these out loud, without looking? If not, re-read that lesson.
- An expression (3x + 2) has no equals sign; an equation (3x + 2 = 11) does — and can be solved.
- Golden rule: whatever you do to one side of an equation, do to the other.
- Undo operations in reverse order: addition/subtraction first, then multiplication/division.
- Collect x-terms on one side before isolating x when unknowns appear on both sides.
- Always check by substituting your answer back into the original equation.
- Watch signs when expanding brackets: a minus outside flips every sign inside.