Year 8 Substitution Worksheet — Level 2 — Answers
Answer sheet with worked solutions for the Year 8 algebraic expressions worksheet.
Year 8 · Mathematics · Algebraic Expressions
Year 8 Substitution Worksheet — Level 2 — Answers
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Replace the letter with the number, then calculate. Use brackets for negative values.
1.Find the value of 3x + 8 when x = −5
Answer: −7
- 3 × (−5) + 8
- = −15 + 8 = −7
2.Find the value of 2x + 6 when x = 5
Answer: 16
- 2 × 5 + 6
- = 10 + 6 = 16
3.Find the value of 7x − 5 when x = 1
Answer: 2
- 7 × 1 − 5
- = 7 − 5 = 2
4.Find the value of −4x + 9 when x = 2
Answer: 1
- −4 × 2 + 9
- = −8 + 9 = 1
5.Find the value of 7x when x = −2
Answer: −14
- 7 × (−2) + 0
- = −14 + 0 = −14
6.Find the value of 9x + 6 when x = 3
Answer: 33
- 9 × 3 + 6
- = 27 + 6 = 33
7.Find the value of 2x + 3 when x = 2
Answer: 7
- 2 × 2 + 3
- = 4 + 3 = 7
8.Find the value of 9x − 7 when x = 8
Answer: 65
- 9 × 8 − 7
- = 72 − 7 = 65
9.Find the value of 2x − 7 when x = −4
Answer: −15
- 2 × (−4) − 7
- = −8 − 7 = −15
10.Find the value of 5x − 3 when x = 4
Answer: 17
- 5 × 4 − 3
- = 20 − 3 = 17
11.Find the value of 5x when x = −5
Answer: −25
- 5 × (−5) + 0
- = −25 + 0 = −25
12.Find the value of x − 2 when x = 5
Answer: 3
- 1 × 5 − 2
- = 5 − 2 = 3
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