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 −2x + 7 when x = 9
Answer: −11
- −2 × 9 + 7
- = −18 + 7 = −11
2.Find the value of 7x − 8 when x = 8
Answer: 48
- 7 × 8 − 8
- = 56 − 8 = 48
3.Find the value of −x − 9 when x = 1
Answer: −10
- −1 × 1 − 9
- = −1 − 9 = −10
4.Find the value of −2x − 3 when x = 2
Answer: −7
- −2 × 2 − 3
- = −4 − 3 = −7
5.Find the value of 6x − 7 when x = 7
Answer: 35
- 6 × 7 − 7
- = 42 − 7 = 35
6.Find the value of x + 2 when x = 4
Answer: 6
- 1 × 4 + 2
- = 4 + 2 = 6
7.Find the value of 5x − 8 when x = 2
Answer: 2
- 5 × 2 − 8
- = 10 − 8 = 2
8.Find the value of −2x + 6 when x = 1
Answer: 4
- −2 × 1 + 6
- = −2 + 6 = 4
9.Find the value of 7x + 8 when x = 5
Answer: 43
- 7 × 5 + 8
- = 35 + 8 = 43
10.Find the value of 5x − 2 when x = 3
Answer: 13
- 5 × 3 − 2
- = 15 − 2 = 13
11.Find the value of 2x + 6 when x = 1
Answer: 8
- 2 × 1 + 6
- = 2 + 6 = 8
12.Find the value of 2x − 4 when x = 6
Answer: 8
- 2 × 6 − 4
- = 12 − 4 = 8
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