Year 9 Factorising Expressions (Common Factors) Worksheet — Level 2 — Practice Set 2 — Answers
Answer sheet with worked solutions for the Year 9 algebraic expressions worksheet.
Year 9 Factorising Expressions (Common Factors) Worksheet — Level 2 — Practice Set 2 — Answers
Find the highest common factor of the terms and write it outside the brackets.
1.Factorise fully: 8x − 48y
Answer: 8(x − 6y)
- Highest common factor: 8
- 8x − 48y = 8(x − 6y)
- Check by expanding the brackets.
2.Factorise fully: 30x2 − 48x
Answer: 6x(5x − 8)
- Highest common factor: 6x
- 30x2 − 48x = 6x(5x − 8)
- Check by expanding the brackets.
3.Factorise fully: 8x − 28y
Answer: 4(2x − 7y)
- Highest common factor: 4
- 8x − 28y = 4(2x − 7y)
- Check by expanding the brackets.
4.Factorise fully: 6x2 − 2x
Answer: 2x(3x − 1)
- Highest common factor: 2x
- 6x2 − 2x = 2x(3x − 1)
- Check by expanding the brackets.
5.Factorise fully: 8m − 2n
Answer: 2(4m − n)
- Highest common factor: 2
- 8m − 2n = 2(4m − n)
- Check by expanding the brackets.
6.Factorise fully: 16x2 − 4x
Answer: 4x(4x − 1)
- Highest common factor: 4x
- 16x2 − 4x = 4x(4x − 1)
- Check by expanding the brackets.
7.Factorise fully: 21x + 49y
Answer: 7(3x + 7y)
- Highest common factor: 7
- 21x + 49y = 7(3x + 7y)
- Check by expanding the brackets.
8.Factorise fully: 4x2 − 2x
Answer: 2x(2x − 1)
- Highest common factor: 2x
- 4x2 − 2x = 2x(2x − 1)
- Check by expanding the brackets.
9.Factorise fully: 8x − 12y
Answer: 4(2x − 3y)
- Highest common factor: 4
- 8x − 12y = 4(2x − 3y)
- Check by expanding the brackets.
10.Factorise fully: 10x2 + 25x
Answer: 5x(2x + 5)
- Highest common factor: 5x
- 10x2 + 25x = 5x(2x + 5)
- Check by expanding the brackets.
11.Factorise fully: 10m + 45n
Answer: 5(2m + 9n)
- Highest common factor: 5
- 10m + 45n = 5(2m + 9n)
- Check by expanding the brackets.
12.Factorise fully: 30x2 + 12x
Answer: 6x(5x + 2)
- Highest common factor: 6x
- 30x2 + 12x = 6x(5x + 2)
- 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.