Year 10 Factorising Expressions (Common Factors) Worksheet — Level 1 — Answers
Answer sheet with worked solutions for the Year 10 algebraic expressions worksheet.
Year 10 Factorising Expressions (Common Factors) Worksheet — Level 1 — Answers
Find the highest common factor of the terms and write it outside the brackets.
1.Factorise fully: 28x − 21
Answer: 7(4x − 3)
- Highest common factor: 7
- 28x − 21 = 7(4x − 3)
- Check by expanding the brackets.
2.Factorise fully: 40x + 64
Answer: 8(5x + 8)
- Highest common factor: 8
- 40x + 64 = 8(5x + 8)
- Check by expanding the brackets.
3.Factorise fully: 12x − 32
Answer: 4(3x − 8)
- Highest common factor: 4
- 12x − 32 = 4(3x − 8)
- Check by expanding the brackets.
4.Factorise fully: 9x + 12
Answer: 3(3x + 4)
- Highest common factor: 3
- 9x + 12 = 3(3x + 4)
- Check by expanding the brackets.
5.Factorise fully: 12x − 2
Answer: 2(6x − 1)
- Highest common factor: 2
- 12x − 2 = 2(6x − 1)
- Check by expanding the brackets.
6.Factorise fully: 12x + 21
Answer: 3(4x + 7)
- Highest common factor: 3
- 12x + 21 = 3(4x + 7)
- Check by expanding the brackets.
7.Factorise fully: 30x − 18
Answer: 6(5x − 3)
- Highest common factor: 6
- 30x − 18 = 6(5x − 3)
- Check by expanding the brackets.
8.Factorise fully: 30x − 36
Answer: 6(5x − 6)
- Highest common factor: 6
- 30x − 36 = 6(5x − 6)
- Check by expanding the brackets.
9.Factorise fully: 35x − 56
Answer: 7(5x − 8)
- Highest common factor: 7
- 35x − 56 = 7(5x − 8)
- Check by expanding the brackets.
10.Factorise fully: 4x + 20
Answer: 4(x + 5)
- Highest common factor: 4
- 4x + 20 = 4(x + 5)
- Check by expanding the brackets.
11.Factorise fully: 7x − 21
Answer: 7(x − 3)
- Highest common factor: 7
- 7x − 21 = 7(x − 3)
- Check by expanding the brackets.
12.Factorise fully: 8x − 72
Answer: 8(x − 9)
- Highest common factor: 8
- 8x − 72 = 8(x − 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.