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 6x − 2 when x = 6
Answer: 34
- 6 × 6 − 2
- = 36 − 2 = 34
2.Find the value of −4x + 6 when x = 7
Answer: −22
- −4 × 7 + 6
- = −28 + 6 = −22
3.Find the value of 5x + 7 when x = 9
Answer: 52
- 5 × 9 + 7
- = 45 + 7 = 52
4.Find the value of −x − 8 when x = 8
Answer: −16
- −1 × 8 − 8
- = −8 − 8 = −16
5.Find the value of 5x + 7 when x = 6
Answer: 37
- 5 × 6 + 7
- = 30 + 7 = 37
6.Find the value of −4x − 8 when x = 3
Answer: −20
- −4 × 3 − 8
- = −12 − 8 = −20
7.Find the value of 3x − 8 when x = 2
Answer: −2
- 3 × 2 − 8
- = 6 − 8 = −2
8.Find the value of 7x + 1 when x = 3
Answer: 22
- 7 × 3 + 1
- = 21 + 1 = 22
9.Find the value of 4x + 4 when x = 6
Answer: 28
- 4 × 6 + 4
- = 24 + 4 = 28
10.Find the value of 7x + 9 when x = 8
Answer: 65
- 7 × 8 + 9
- = 56 + 9 = 65
11.Find the value of −4x + 6 when x = 5
Answer: −14
- −4 × 5 + 6
- = −20 + 6 = −14
12.Find the value of −5x + 3 when x = 2
Answer: −7
- −5 × 2 + 3
- = −10 + 3 = −7
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