Year 10 Factorising Expressions (Common Factors) Worksheet — Level 3 — Practice Set 2 — Answers
Answer sheet with worked solutions for the Year 10 algebraic expressions worksheet.
Year 10 Factorising Expressions (Common Factors) Worksheet — Level 3 — Practice Set 2 — Answers
Take out the highest common factor. Where the first term is negative, take out a negative factor.
1.Factorise fully: −2x − 2
Answer: −2(x + 1)
- Highest common factor: −2
- −2x − 2 = −2(x + 1)
- Check by expanding the brackets.
2.Factorise fully: 6x2 − 12x − 10
Answer: 2(3x2−6x−5)
- Highest common factor: 2
- 6x2 − 12x − 10 = 2(3x2 − 6x − 5)
- Check by expanding the brackets.
3.Factorise fully: 3ab + 18a
Answer: 3a(b + 6)
- Highest common factor: 3a
- 3ab + 18a = 3a(b + 6)
- Check by expanding the brackets.
4.Factorise fully: −12x − 20
Answer: −4(3x + 5)
- Highest common factor: −4
- −12x − 20 = −4(3x + 5)
- Check by expanding the brackets.
5.Factorise fully: 24x2 + 42x − 36
Answer: 6(4x2+7x−6)
- Highest common factor: 6
- 24x2 + 42x − 36 = 6(4x2 + 7x − 6)
- Check by expanding the brackets.
6.Factorise fully: 12ab − 15a
Answer: 3a(4b − 5)
- Highest common factor: 3a
- 12ab − 15a = 3a(4b − 5)
- Check by expanding the brackets.
7.Factorise fully: −2x − 14
Answer: −2(x + 7)
- Highest common factor: −2
- −2x − 14 = −2(x + 7)
- Check by expanding the brackets.
8.Factorise fully: 2x2 + 8x + 14
Answer: 2(x2+4x+7)
- Highest common factor: 2
- 2x2 + 8x + 14 = 2(x2 + 4x + 7)
- Check by expanding the brackets.
9.Factorise fully: 24ab − 30a
Answer: 6a(4b − 5)
- Highest common factor: 6a
- 24ab − 30a = 6a(4b − 5)
- Check by expanding the brackets.
10.Factorise fully: −24x + 4
Answer: −4(6x − 1)
- Highest common factor: −4
- −24x + 4 = −4(6x − 1)
- Check by expanding the brackets.
11.Factorise fully: 4x2 − 16x − 16
Answer: 4(x2−4x−4)
- Highest common factor: 4
- 4x2 − 16x − 16 = 4(x2 − 4x − 4)
- Check by expanding the brackets.
12.Factorise fully: 12ab − 20a
Answer: 4a(3b − 5)
- Highest common factor: 4a
- 12ab − 20a = 4a(3b − 5)
- 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.