Year 8 Substitution Worksheet — Level 1 — Answers
Answer sheet with worked solutions for the Year 8 algebraic expressions worksheet.
Success TutoringWorksheetsAnswer sheetYear 8 · Mathematics · Algebraic ExpressionsYear 8 Substitution Worksheet — Level 1 — Answers
Replace the letter with the number, then calculate. Use brackets for negative values.
1.Find the value of −2x − 6 when x = 1
Answer: −8
- −2 × 1 − 6
- = −2 − 6 = −8
2.Find the value of x when x = 9
Answer: 9
- 1 × 9 + 0
- = 9 + 0 = 9
3.Find the value of 4x + 5 when x = 4
Answer: 21
- 4 × 4 + 5
- = 16 + 5 = 21
4.Find the value of 5x + 5 when x = 6
Answer: 35
- 5 × 6 + 5
- = 30 + 5 = 35
5.Find the value of 9x + 7 when x = 1
Answer: 16
- 9 × 1 + 7
- = 9 + 7 = 16
6.Find the value of 5x − 1 when x = 8
Answer: 39
- 5 × 8 − 1
- = 40 − 1 = 39
7.Find the value of 4x − 2 when x = 3
Answer: 10
- 4 × 3 − 2
- = 12 − 2 = 10
8.Find the value of 7x − 8 when x = 7
Answer: 41
- 7 × 7 − 8
- = 49 − 8 = 41
9.Find the value of 5x + 5 when x = 2
Answer: 15
- 5 × 2 + 5
- = 10 + 5 = 15
10.Find the value of −x + 4 when x = 5
Answer: −1
- −1 × 5 + 4
- = −5 + 4 = −1
11.Find the value of −3x + 3 when x = 6
Answer: −15
- −3 × 6 + 3
- = −18 + 3 = −15
12.Find the value of x − 1 when x = 6
Answer: 5
- 1 × 6 − 1
- = 6 − 1 = 5
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