Year 8 Substitution Worksheet — Level 2 — Practice Set 3 — 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 3 — Answers
Replace the letter with the number, then calculate. Use brackets for negative values.
1.Find the value of 2x + 2 when x = −1
Answer: 0
- 2 × (−1) + 2
- = −2 + 2 = 0
2.Find the value of 9x − 1 when x = −5
Answer: −46
- 9 × (−5) − 1
- = −45 − 1 = −46
3.Find the value of 3x + 5 when x = 2
Answer: 11
- 3 × 2 + 5
- = 6 + 5 = 11
4.Find the value of 3x + 3 when x = 9
Answer: 30
- 3 × 9 + 3
- = 27 + 3 = 30
5.Find the value of 7x + 8 when x = 6
Answer: 50
- 7 × 6 + 8
- = 42 + 8 = 50
6.Find the value of 9x + 9 when x = 7
Answer: 72
- 9 × 7 + 9
- = 63 + 9 = 72
7.Find the value of −3x − 2 when x = 5
Answer: −17
- −3 × 5 − 2
- = −15 − 2 = −17
8.Find the value of 5x + 7 when x = 6
Answer: 37
- 5 × 6 + 7
- = 30 + 7 = 37
9.Find the value of −x − 1 when x = 6
Answer: −7
- −1 × 6 − 1
- = −6 − 1 = −7
10.Find the value of 9x + 3 when x = 6
Answer: 57
- 9 × 6 + 3
- = 54 + 3 = 57
11.Find the value of 2x + 8 when x = 4
Answer: 16
- 2 × 4 + 8
- = 8 + 8 = 16
12.Find the value of 3x − 6 when x = −4
Answer: −18
- 3 × (−4) − 6
- = −12 − 6 = −18
Marking tips
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