Year 8 Factorising Expressions (Common Factors) Worksheet — Level 1 — Practice Set 3 — Answers
Answer sheet with worked solutions for the Year 8 algebraic expressions worksheet.
Year 8 Factorising Expressions (Common Factors) Worksheet — Level 1 — Practice Set 3 — Answers
Find the highest common factor of the terms and write it outside the brackets.
1.Factorise fully: 35x − 56
Answer: 7(5x − 8)
- Highest common factor: 7
- 35x − 56 = 7(5x − 8)
- Check by expanding the brackets.
2.Factorise fully: 9x + 18
Answer: 9(x + 2)
- Highest common factor: 9
- 9x + 18 = 9(x + 2)
- Check by expanding the brackets.
3.Factorise fully: 16x − 36
Answer: 4(4x − 9)
- Highest common factor: 4
- 16x − 36 = 4(4x − 9)
- Check by expanding the brackets.
4.Factorise fully: 30x − 36
Answer: 6(5x − 6)
- Highest common factor: 6
- 30x − 36 = 6(5x − 6)
- Check by expanding the brackets.
5.Factorise fully: 6x − 42
Answer: 6(x − 7)
- Highest common factor: 6
- 6x − 42 = 6(x − 7)
- Check by expanding the brackets.
6.Factorise fully: 6x + 27
Answer: 3(2x + 9)
- Highest common factor: 3
- 6x + 27 = 3(2x + 9)
- Check by expanding the brackets.
7.Factorise fully: 7x − 7
Answer: 7(x − 1)
- Highest common factor: 7
- 7x − 7 = 7(x − 1)
- Check by expanding the brackets.
8.Factorise fully: 3x + 18
Answer: 3(x + 6)
- Highest common factor: 3
- 3x + 18 = 3(x + 6)
- Check by expanding the brackets.
9.Factorise fully: 6x + 21
Answer: 3(2x + 7)
- Highest common factor: 3
- 6x + 21 = 3(2x + 7)
- Check by expanding the brackets.
10.Factorise fully: 16x − 12
Answer: 4(4x − 3)
- Highest common factor: 4
- 16x − 12 = 4(4x − 3)
- Check by expanding the brackets.
11.Factorise fully: 24x − 64
Answer: 8(3x − 8)
- Highest common factor: 8
- 24x − 64 = 8(3x − 8)
- Check by expanding the brackets.
12.Factorise fully: 24x + 28
Answer: 4(6x + 7)
- Highest common factor: 4
- 24x + 28 = 4(6x + 7)
- 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.