Year 9 Substitution Worksheet — Level 1 — 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 1 — Practice Set 4 — Answers
Replace the letter with the number, then calculate. Use brackets for negative values.
1.Find the value of −x + 2 when x = 8
Answer: −6
- −1 × 8 + 2
- = −8 + 2 = −6
2.Find the value of −3x + 6 when x = 7
Answer: −15
- −3 × 7 + 6
- = −21 + 6 = −15
3.Find the value of −3x − 6 when x = 1
Answer: −9
- −3 × 1 − 6
- = −3 − 6 = −9
4.Find the value of 4x − 3 when x = 7
Answer: 25
- 4 × 7 − 3
- = 28 − 3 = 25
5.Find the value of 9x − 2 when x = 3
Answer: 25
- 9 × 3 − 2
- = 27 − 2 = 25
6.Find the value of −x − 1 when x = 1
Answer: −2
- −1 × 1 − 1
- = −1 − 1 = −2
7.Find the value of 3x − 8 when x = 3
Answer: 1
- 3 × 3 − 8
- = 9 − 8 = 1
8.Find the value of −2x + 8 when x = 1
Answer: 6
- −2 × 1 + 8
- = −2 + 8 = 6
9.Find the value of 3x − 1 when x = 2
Answer: 5
- 3 × 2 − 1
- = 6 − 1 = 5
10.Find the value of x − 3 when x = 2
Answer: −1
- 1 × 2 − 3
- = 2 − 3 = −1
11.Find the value of −5x − 8 when x = 4
Answer: −28
- −5 × 4 − 8
- = −20 − 8 = −28
12.Find the value of x − 6 when x = 5
Answer: −1
- 1 × 5 − 6
- = 5 − 6 = −1
Marking tips
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