Year 8 Substitution Worksheet — Level 1 — Practice Set 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 1 — Practice Set 2 — Answers
Replace the letter with the number, then calculate. Use brackets for negative values.
1.Find the value of −5x + 7 when x = 7
Answer: −28
- −5 × 7 + 7
- = −35 + 7 = −28
2.Find the value of 2x + 5 when x = 6
Answer: 17
- 2 × 6 + 5
- = 12 + 5 = 17
3.Find the value of 2x + 8 when x = 5
Answer: 18
- 2 × 5 + 8
- = 10 + 8 = 18
4.Find the value of 8x − 4 when x = 1
Answer: 4
- 8 × 1 − 4
- = 8 − 4 = 4
5.Find the value of x − 9 when x = 7
Answer: −2
- 1 × 7 − 9
- = 7 − 9 = −2
6.Find the value of 2x + 2 when x = 5
Answer: 12
- 2 × 5 + 2
- = 10 + 2 = 12
7.Find the value of 7x + 7 when x = 1
Answer: 14
- 7 × 1 + 7
- = 7 + 7 = 14
8.Find the value of 7x − 3 when x = 3
Answer: 18
- 7 × 3 − 3
- = 21 − 3 = 18
9.Find the value of 6x − 6 when x = 9
Answer: 48
- 6 × 9 − 6
- = 54 − 6 = 48
10.Find the value of −5x − 3 when x = 4
Answer: −23
- −5 × 4 − 3
- = −20 − 3 = −23
11.Find the value of −2x + 8 when x = 8
Answer: −8
- −2 × 8 + 8
- = −16 + 8 = −8
12.Find the value of −2x + 9 when x = 4
Answer: 1
- −2 × 4 + 9
- = −8 + 9 = 1
Marking tips
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