Year 9 Factorising Expressions (Common Factors) Worksheet — Level 2 — Answers
Answer sheet with worked solutions for the Year 9 algebraic expressions worksheet.
Year 9 Factorising Expressions (Common Factors) Worksheet — Level 2 — Answers
Find the highest common factor of the terms and write it outside the brackets.
1.Factorise fully: 4a − 6b
Answer: 2(2a − 3b)
- Highest common factor: 2
- 4a − 6b = 2(2a − 3b)
- Check by expanding the brackets.
2.Factorise fully: 8x2 − 18x
Answer: 2x(4x − 9)
- Highest common factor: 2x
- 8x2 − 18x = 2x(4x − 9)
- Check by expanding the brackets.
3.Factorise fully: 32m − 24n
Answer: 8(4m − 3n)
- Highest common factor: 8
- 32m − 24n = 8(4m − 3n)
- Check by expanding the brackets.
4.Factorise fully: 6x2 + 4x
Answer: 2x(3x + 2)
- Highest common factor: 2x
- 6x2 + 4x = 2x(3x + 2)
- Check by expanding the brackets.
5.Factorise fully: 14m + 35n
Answer: 7(2m + 5n)
- Highest common factor: 7
- 14m + 35n = 7(2m + 5n)
- Check by expanding the brackets.
6.Factorise fully: 2x2 + 16x
Answer: 2x(x + 8)
- Highest common factor: 2x
- 2x2 + 16x = 2x(x + 8)
- Check by expanding the brackets.
7.Factorise fully: 20x − 28y
Answer: 4(5x − 7y)
- Highest common factor: 4
- 20x − 28y = 4(5x − 7y)
- Check by expanding the brackets.
8.Factorise fully: 3x2 − 12x
Answer: 3x(x − 4)
- Highest common factor: 3x
- 3x2 − 12x = 3x(x − 4)
- Check by expanding the brackets.
9.Factorise fully: 40a + 64b
Answer: 8(5a + 8b)
- Highest common factor: 8
- 40a + 64b = 8(5a + 8b)
- Check by expanding the brackets.
10.Factorise fully: 2x2 − 12x
Answer: 2x(x − 6)
- Highest common factor: 2x
- 2x2 − 12x = 2x(x − 6)
- Check by expanding the brackets.
11.Factorise fully: 42x − 7y
Answer: 7(6x − y)
- Highest common factor: 7
- 42x − 7y = 7(6x − y)
- Check by expanding the brackets.
12.Factorise fully: 20x2 − 45x
Answer: 5x(4x − 9)
- Highest common factor: 5x
- 20x2 − 45x = 5x(4x − 9)
- Check by expanding the brackets.
Marking tips
- Give credit for correct method even when the final answer slips — the working shows where the thinking went right.
- For open-ended tasks, use the success criteria as a checklist rather than looking for one "right" answer.
- Celebrate what went well first, then pick one thing to work on next.