Year 8 Substitution Worksheet — Level 2 — Practice Set 2 — Answers
Answer sheet with worked solutions for the Year 8 algebraic expressions worksheet.
Success TutoringWorksheetsAnswer sheetYear 8 · Mathematics · Algebraic ExpressionsYear 8 Substitution Worksheet — Level 2 — Practice Set 2 — Answers
Replace the letter with the number, then calculate. Use brackets for negative values.
1.Find the value of x − 9 when x = 1
Answer: −8
- 1 × 1 − 9
- = 1 − 9 = −8
2.Find the value of 3x − 6 when x = 4
Answer: 6
- 3 × 4 − 6
- = 12 − 6 = 6
3.Find the value of 8x − 6 when x = −1
Answer: −14
- 8 × (−1) − 6
- = −8 − 6 = −14
4.Find the value of 3x + 8 when x = 4
Answer: 20
- 3 × 4 + 8
- = 12 + 8 = 20
5.Find the value of 8x − 8 when x = 1
Answer: 0
- 8 × 1 − 8
- = 8 − 8 = 0
6.Find the value of −4x − 2 when x = 9
Answer: −38
- −4 × 9 − 2
- = −36 − 2 = −38
7.Find the value of 7x − 8 when x = 9
Answer: 55
- 7 × 9 − 8
- = 63 − 8 = 55
8.Find the value of 9x + 3 when x = 6
Answer: 57
- 9 × 6 + 3
- = 54 + 3 = 57
9.Find the value of 3x + 2 when x = −5
Answer: −13
- 3 × (−5) + 2
- = −15 + 2 = −13
10.Find the value of x − 2 when x = −3
Answer: −5
- 1 × (−3) − 2
- = −3 − 2 = −5
11.Find the value of 5x + 3 when x = 8
Answer: 43
- 5 × 8 + 3
- = 40 + 3 = 43
12.Find the value of 3x − 6 when x = 2
Answer: 0
- 3 × 2 − 6
- = 6 − 6 = 0
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