Year 8 Substitution Worksheet — Level 1 — 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 1 — Practice Set 4 — Answers
Replace the letter with the number, then calculate. Use brackets for negative values.
1.Find the value of −x − 5 when x = 1
Answer: −6
- −1 × 1 − 5
- = −1 − 5 = −6
2.Find the value of −5x + 2 when x = 8
Answer: −38
- −5 × 8 + 2
- = −40 + 2 = −38
3.Find the value of 2x + 7 when x = 7
Answer: 21
- 2 × 7 + 7
- = 14 + 7 = 21
4.Find the value of 9x − 3 when x = 9
Answer: 78
- 9 × 9 − 3
- = 81 − 3 = 78
5.Find the value of 4x + 4 when x = 1
Answer: 8
- 4 × 1 + 4
- = 4 + 4 = 8
6.Find the value of 2x when x = 5
Answer: 10
- 2 × 5 + 0
- = 10 + 0 = 10
7.Find the value of 4x + 2 when x = 7
Answer: 30
- 4 × 7 + 2
- = 28 + 2 = 30
8.Find the value of 5x + 7 when x = 7
Answer: 42
- 5 × 7 + 7
- = 35 + 7 = 42
9.Find the value of 3x − 9 when x = 9
Answer: 18
- 3 × 9 − 9
- = 27 − 9 = 18
10.Find the value of 4x when x = 2
Answer: 8
- 4 × 2 + 0
- = 8 + 0 = 8
11.Find the value of 5x + 7 when x = 1
Answer: 12
- 5 × 1 + 7
- = 5 + 7 = 12
12.Find the value of 8x + 5 when x = 8
Answer: 69
- 8 × 8 + 5
- = 64 + 5 = 69
Marking tips
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