Year 8 Substitution Worksheet — Level 1 — Practice Set 3 — 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 3 — Answers
Replace the letter with the number, then calculate. Use brackets for negative values.
1.Find the value of −x − 7 when x = 8
Answer: −15
- −1 × 8 − 7
- = −8 − 7 = −15
2.Find the value of 9x + 9 when x = 9
Answer: 90
- 9 × 9 + 9
- = 81 + 9 = 90
3.Find the value of −5x − 2 when x = 8
Answer: −42
- −5 × 8 − 2
- = −40 − 2 = −42
4.Find the value of 2x − 3 when x = 1
Answer: −1
- 2 × 1 − 3
- = 2 − 3 = −1
5.Find the value of 7x + 1 when x = 2
Answer: 15
- 7 × 2 + 1
- = 14 + 1 = 15
6.Find the value of −4x − 7 when x = 4
Answer: −23
- −4 × 4 − 7
- = −16 − 7 = −23
7.Find the value of x + 4 when x = 3
Answer: 7
- 1 × 3 + 4
- = 3 + 4 = 7
8.Find the value of 6x + 2 when x = 8
Answer: 50
- 6 × 8 + 2
- = 48 + 2 = 50
9.Find the value of 5x − 4 when x = 2
Answer: 6
- 5 × 2 − 4
- = 10 − 4 = 6
10.Find the value of −5x − 8 when x = 9
Answer: −53
- −5 × 9 − 8
- = −45 − 8 = −53
11.Find the value of −x + 5 when x = 8
Answer: −3
- −1 × 8 + 5
- = −8 + 5 = −3
12.Find the value of 3x + 5 when x = 6
Answer: 23
- 3 × 6 + 5
- = 18 + 5 = 23
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