Year 8 Substitution Worksheet — Level 2 — Practice Set 4 — Answers
Answer sheet with worked solutions for the Year 8 algebraic expressions worksheet.
Success TutoringWorksheetsAnswer sheetYear 8 · Mathematics · Algebraic ExpressionsYear 8 Substitution Worksheet — Level 2 — Practice Set 4 — Answers
Replace the letter with the number, then calculate. Use brackets for negative values.
1.Find the value of −2x + 6 when x = 7
Answer: −8
- −2 × 7 + 6
- = −14 + 6 = −8
2.Find the value of −5x + 9 when x = −5
Answer: 34
- −5 × (−5) + 9
- = 25 + 9 = 34
3.Find the value of −x − 6 when x = 6
Answer: −12
- −1 × 6 − 6
- = −6 − 6 = −12
4.Find the value of 6x − 6 when x = 9
Answer: 48
- 6 × 9 − 6
- = 54 − 6 = 48
5.Find the value of 4x + 9 when x = −5
Answer: −11
- 4 × (−5) + 9
- = −20 + 9 = −11
6.Find the value of 6x − 4 when x = −1
Answer: −10
- 6 × (−1) − 4
- = −6 − 4 = −10
7.Find the value of −5x + 1 when x = 3
Answer: −14
- −5 × 3 + 1
- = −15 + 1 = −14
8.Find the value of −2x + 1 when x = 2
Answer: −3
- −2 × 2 + 1
- = −4 + 1 = −3
9.Find the value of −x − 1 when x = 8
Answer: −9
- −1 × 8 − 1
- = −8 − 1 = −9
10.Find the value of −2x − 3 when x = −6
Answer: 9
- −2 × (−6) − 3
- = 12 − 3 = 9
11.Find the value of 5x + 5 when x = 3
Answer: 20
- 5 × 3 + 5
- = 15 + 5 = 20
12.Find the value of 4x − 4 when x = 9
Answer: 32
- 4 × 9 − 4
- = 36 − 4 = 32
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.