Year 8 Substitution Worksheet — Level 2 — 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 2 — Practice Set 4 — Answers
Replace the letter with the number, then calculate. Use brackets for negative values.
1.Find the value of −2x + 9 when x = 5
Answer: −1
- −2 × 5 + 9
- = −10 + 9 = −1
2.Find the value of x − 9 when x = 5
Answer: −4
- 1 × 5 − 9
- = 5 − 9 = −4
3.Find the value of 5x + 6 when x = 1
Answer: 11
- 5 × 1 + 6
- = 5 + 6 = 11
4.Find the value of 4x + 5 when x = 6
Answer: 29
- 4 × 6 + 5
- = 24 + 5 = 29
5.Find the value of −x + 6 when x = 4
Answer: 2
- −1 × 4 + 6
- = −4 + 6 = 2
6.Find the value of 7x + 1 when x = 1
Answer: 8
- 7 × 1 + 1
- = 7 + 1 = 8
7.Find the value of 5x − 8 when x = −6
Answer: −38
- 5 × (−6) − 8
- = −30 − 8 = −38
8.Find the value of x − 5 when x = 5
Answer: 0
- 1 × 5 − 5
- = 5 − 5 = 0
9.Find the value of −3x − 8 when x = −3
Answer: 1
- −3 × (−3) − 8
- = 9 − 8 = 1
10.Find the value of −2x + 5 when x = 8
Answer: −11
- −2 × 8 + 5
- = −16 + 5 = −11
11.Find the value of 6x − 6 when x = −4
Answer: −30
- 6 × (−4) − 6
- = −24 − 6 = −30
12.Find the value of 7x − 5 when x = 4
Answer: 23
- 7 × 4 − 5
- = 28 − 5 = 23
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