Year 8 Substitution Worksheet — Level 1 — Answers
Answer sheet with worked solutions for the Year 8 algebraic expressions worksheet.
Year 8 · Mathematics · Algebraic Expressions
Year 8 Substitution Worksheet — Level 1 — Answers
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Replace the letter with the number, then calculate. Use brackets for negative values.
1.Find the value of 6x − 1 when x = 6
Answer: 35
- 6 × 6 − 1
- = 36 − 1 = 35
2.Find the value of 9x + 9 when x = 8
Answer: 81
- 9 × 8 + 9
- = 72 + 9 = 81
3.Find the value of −3x − 8 when x = 2
Answer: −14
- −3 × 2 − 8
- = −6 − 8 = −14
4.Find the value of −5x + 7 when x = 2
Answer: −3
- −5 × 2 + 7
- = −10 + 7 = −3
5.Find the value of 5x − 4 when x = 9
Answer: 41
- 5 × 9 − 4
- = 45 − 4 = 41
6.Find the value of 8x − 3 when x = 4
Answer: 29
- 8 × 4 − 3
- = 32 − 3 = 29
7.Find the value of 4x − 9 when x = 1
Answer: −5
- 4 × 1 − 9
- = 4 − 9 = −5
8.Find the value of 5x + 7 when x = 5
Answer: 32
- 5 × 5 + 7
- = 25 + 7 = 32
9.Find the value of 7x − 8 when x = 6
Answer: 34
- 7 × 6 − 8
- = 42 − 8 = 34
10.Find the value of 8x − 1 when x = 2
Answer: 15
- 8 × 2 − 1
- = 16 − 1 = 15
11.Find the value of 2x − 1 when x = 1
Answer: 1
- 2 × 1 − 1
- = 2 − 1 = 1
12.Find the value of 6x + 7 when x = 5
Answer: 37
- 6 × 5 + 7
- = 30 + 7 = 37
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