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 7x − 1 when x = 7
Answer: 48
- 7 × 7 − 1
- = 49 − 1 = 48
2.Find the value of x − 7 when x = 9
Answer: 2
- 1 × 9 − 7
- = 9 − 7 = 2
3.Find the value of 8x − 4 when x = 7
Answer: 52
- 8 × 7 − 4
- = 56 − 4 = 52
4.Find the value of 3x + 4 when x = 1
Answer: 7
- 3 × 1 + 4
- = 3 + 4 = 7
5.Find the value of −5x + 8 when x = 3
Answer: −7
- −5 × 3 + 8
- = −15 + 8 = −7
6.Find the value of −3x + 5 when x = 4
Answer: −7
- −3 × 4 + 5
- = −12 + 5 = −7
7.Find the value of −2x + 8 when x = 3
Answer: 2
- −2 × 3 + 8
- = −6 + 8 = 2
8.Find the value of 7x − 7 when x = 3
Answer: 14
- 7 × 3 − 7
- = 21 − 7 = 14
9.Find the value of 7x + 2 when x = 7
Answer: 51
- 7 × 7 + 2
- = 49 + 2 = 51
10.Find the value of 2x − 2 when x = 7
Answer: 12
- 2 × 7 − 2
- = 14 − 2 = 12
11.Find the value of −x + 7 when x = 6
Answer: 1
- −1 × 6 + 7
- = −6 + 7 = 1
12.Find the value of −x − 8 when x = 1
Answer: −9
- −1 × 1 − 8
- = −1 − 8 = −9
Marking tips
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