Year 9 Substitution Worksheet — Level 1 — 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 1 — Practice Set 3 — Answers
Replace the letter with the number, then calculate. Use brackets for negative values.
1.Find the value of −5x − 7 when x = 8
Answer: −47
- −5 × 8 − 7
- = −40 − 7 = −47
2.Find the value of 2x + 7 when x = 1
Answer: 9
- 2 × 1 + 7
- = 2 + 7 = 9
3.Find the value of −x − 6 when x = 2
Answer: −8
- −1 × 2 − 6
- = −2 − 6 = −8
4.Find the value of 9x + 6 when x = 8
Answer: 78
- 9 × 8 + 6
- = 72 + 6 = 78
5.Find the value of 7x − 4 when x = 5
Answer: 31
- 7 × 5 − 4
- = 35 − 4 = 31
6.Find the value of −4x when x = 3
Answer: −12
- −4 × 3 + 0
- = −12 + 0 = −12
7.Find the value of −x − 7 when x = 6
Answer: −13
- −1 × 6 − 7
- = −6 − 7 = −13
8.Find the value of 7x − 1 when x = 6
Answer: 41
- 7 × 6 − 1
- = 42 − 1 = 41
9.Find the value of 9x − 4 when x = 9
Answer: 77
- 9 × 9 − 4
- = 81 − 4 = 77
10.Find the value of x when x = 3
Answer: 3
- 1 × 3 + 0
- = 3 + 0 = 3
11.Find the value of 2x + 3 when x = 4
Answer: 11
- 2 × 4 + 3
- = 8 + 3 = 11
12.Find the value of −2x − 9 when x = 5
Answer: −19
- −2 × 5 − 9
- = −10 − 9 = −19
Marking tips
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