Year 10 Factorising Expressions (Common Factors) Worksheet — Level 3 — Answers
Answer sheet with worked solutions for the Year 10 algebraic expressions worksheet.
Year 10 Factorising Expressions (Common Factors) Worksheet — Level 3 — Answers
Take out the highest common factor. Where the first term is negative, take out a negative factor.
1.Factorise fully: −32x + 8
Answer: −8(4x − 1)
- Highest common factor: −8
- −32x + 8 = −8(4x − 1)
- Check by expanding the brackets.
2.Factorise fully: 6x2 − 36x − 36
Answer: 6(x2−6x−6)
- Highest common factor: 6
- 6x2 − 36x − 36 = 6(x2 − 6x − 6)
- Check by expanding the brackets.
3.Factorise fully: 4ab + 16a
Answer: 4a(b + 4)
- Highest common factor: 4a
- 4ab + 16a = 4a(b + 4)
- Check by expanding the brackets.
4.Factorise fully: −4x + 4
Answer: −4(x − 1)
- Highest common factor: −4
- −4x + 4 = −4(x − 1)
- Check by expanding the brackets.
5.Factorise fully: 4x2 + 12x + 36
Answer: 4(x2+3x+9)
- Highest common factor: 4
- 4x2 + 12x + 36 = 4(x2 + 3x + 9)
- Check by expanding the brackets.
6.Factorise fully: 15ab + 35a
Answer: 5a(3b + 7)
- Highest common factor: 5a
- 15ab + 35a = 5a(3b + 7)
- Check by expanding the brackets.
7.Factorise fully: −6x + 4
Answer: −2(3x − 2)
- Highest common factor: −2
- −6x + 4 = −2(3x − 2)
- Check by expanding the brackets.
8.Factorise fully: 12x2 + 16x + 24
Answer: 4(3x2+4x+6)
- Highest common factor: 4
- 12x2 + 16x + 24 = 4(3x2 + 4x + 6)
- Check by expanding the brackets.
9.Factorise fully: 15ab − 18a
Answer: 3a(5b − 6)
- Highest common factor: 3a
- 15ab − 18a = 3a(5b − 6)
- Check by expanding the brackets.
10.Factorise fully: −16x − 8
Answer: −8(2x + 1)
- Highest common factor: −8
- −16x − 8 = −8(2x + 1)
- Check by expanding the brackets.
11.Factorise fully: 18x2 + 42x − 6
Answer: 6(3x2+7x−1)
- Highest common factor: 6
- 18x2 + 42x − 6 = 6(3x2 + 7x − 1)
- Check by expanding the brackets.
12.Factorise fully: 4ab − 12a
Answer: 4a(b − 3)
- Highest common factor: 4a
- 4ab − 12a = 4a(b − 3)
- 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.