Year 9 Substitution Worksheet — Level 2 — Practice Set 4 — Answers
Answer sheet with worked solutions for the Year 9 algebraic expressions worksheet.
Success TutoringWorksheetsAnswer sheetYear 9 · Mathematics · Algebraic ExpressionsYear 9 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 5x when x = −1
Answer: −5
- 5 × (−1) + 0
- = −5 + 0 = −5
2.Find the value of 8x + 1 when x = 3
Answer: 25
- 8 × 3 + 1
- = 24 + 1 = 25
3.Find the value of 5x − 5 when x = −6
Answer: −35
- 5 × (−6) − 5
- = −30 − 5 = −35
4.Find the value of 8x − 1 when x = −5
Answer: −41
- 8 × (−5) − 1
- = −40 − 1 = −41
5.Find the value of x when x = −1
Answer: −1
- 1 × (−1) + 0
- = −1 + 0 = −1
6.Find the value of 3x + 8 when x = −6
Answer: −10
- 3 × (−6) + 8
- = −18 + 8 = −10
7.Find the value of x when x = −3
Answer: −3
- 1 × (−3) + 0
- = −3 + 0 = −3
8.Find the value of −3x + 4 when x = 5
Answer: −11
- −3 × 5 + 4
- = −15 + 4 = −11
9.Find the value of 2x − 4 when x = −2
Answer: −8
- 2 × (−2) − 4
- = −4 − 4 = −8
10.Find the value of −x − 6 when x = −3
Answer: −3
- −1 × (−3) − 6
- = 3 − 6 = −3
11.Find the value of −x + 4 when x = 5
Answer: −1
- −1 × 5 + 4
- = −5 + 4 = −1
12.Find the value of 3x + 7 when x = −1
Answer: 4
- 3 × (−1) + 7
- = −3 + 7 = 4
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