Year 8 Substitution Worksheet — Level 2 — 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 — Answers
Replace the letter with the number, then calculate. Use brackets for negative values.
1.Find the value of 5x + 1 when x = −4
Answer: −19
- 5 × (−4) + 1
- = −20 + 1 = −19
2.Find the value of −3x when x = −4
Answer: 12
- −3 × (−4) + 0
- = 12 + 0 = 12
3.Find the value of −2x + 6 when x = −1
Answer: 8
- −2 × (−1) + 6
- = 2 + 6 = 8
4.Find the value of 3x + 5 when x = 9
Answer: 32
- 3 × 9 + 5
- = 27 + 5 = 32
5.Find the value of 4x − 9 when x = 9
Answer: 27
- 4 × 9 − 9
- = 36 − 9 = 27
6.Find the value of −5x − 6 when x = −1
Answer: −1
- −5 × (−1) − 6
- = 5 − 6 = −1
7.Find the value of −2x − 8 when x = 7
Answer: −22
- −2 × 7 − 8
- = −14 − 8 = −22
8.Find the value of 7x when x = 7
Answer: 49
- 7 × 7 + 0
- = 49 + 0 = 49
9.Find the value of 7x + 6 when x = 4
Answer: 34
- 7 × 4 + 6
- = 28 + 6 = 34
10.Find the value of 9x − 1 when x = −5
Answer: −46
- 9 × (−5) − 1
- = −45 − 1 = −46
11.Find the value of 6x − 7 when x = 4
Answer: 17
- 6 × 4 − 7
- = 24 − 7 = 17
12.Find the value of −x + 7 when x = 5
Answer: 2
- −1 × 5 + 7
- = −5 + 7 = 2
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