Year 9 Substitution Worksheet — Level 2 — Practice Set 3 — 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 3 — Answers
Replace the letter with the number, then calculate. Use brackets for negative values.
1.Find the value of 2x + 5 when x = 3
Answer: 11
- 2 × 3 + 5
- = 6 + 5 = 11
2.Find the value of 5x + 7 when x = −4
Answer: −13
- 5 × (−4) + 7
- = −20 + 7 = −13
3.Find the value of 2x − 8 when x = −4
Answer: −16
- 2 × (−4) − 8
- = −8 − 8 = −16
4.Find the value of 5x + 1 when x = 2
Answer: 11
- 5 × 2 + 1
- = 10 + 1 = 11
5.Find the value of −3x − 2 when x = 1
Answer: −5
- −3 × 1 − 2
- = −3 − 2 = −5
6.Find the value of 4x + 7 when x = −2
Answer: −1
- 4 × (−2) + 7
- = −8 + 7 = −1
7.Find the value of 6x − 5 when x = 6
Answer: 31
- 6 × 6 − 5
- = 36 − 5 = 31
8.Find the value of −x when x = 4
Answer: −4
- −1 × 4 + 0
- = −4 + 0 = −4
9.Find the value of x + 1 when x = −4
Answer: −3
- 1 × (−4) + 1
- = −4 + 1 = −3
10.Find the value of 8x + 4 when x = 1
Answer: 12
- 8 × 1 + 4
- = 8 + 4 = 12
11.Find the value of 3x + 1 when x = −5
Answer: −14
- 3 × (−5) + 1
- = −15 + 1 = −14
12.Find the value of 7x when x = −4
Answer: −28
- 7 × (−4) + 0
- = −28 + 0 = −28
Marking tips
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