Year 8 Substitution Worksheet — Level 2 — Practice Set 3 — 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 3 — Answers
Replace the letter with the number, then calculate. Use brackets for negative values.
1.Find the value of 4x − 6 when x = 8
Answer: 26
- 4 × 8 − 6
- = 32 − 6 = 26
2.Find the value of 2x − 6 when x = 6
Answer: 6
- 2 × 6 − 6
- = 12 − 6 = 6
3.Find the value of 5x − 6 when x = 6
Answer: 24
- 5 × 6 − 6
- = 30 − 6 = 24
4.Find the value of x + 8 when x = 1
Answer: 9
- 1 × 1 + 8
- = 1 + 8 = 9
5.Find the value of 9x + 4 when x = −2
Answer: −14
- 9 × (−2) + 4
- = −18 + 4 = −14
6.Find the value of −x − 5 when x = 6
Answer: −11
- −1 × 6 − 5
- = −6 − 5 = −11
7.Find the value of 7x + 5 when x = −3
Answer: −16
- 7 × (−3) + 5
- = −21 + 5 = −16
8.Find the value of 8x + 5 when x = 9
Answer: 77
- 8 × 9 + 5
- = 72 + 5 = 77
9.Find the value of 4x + 3 when x = 4
Answer: 19
- 4 × 4 + 3
- = 16 + 3 = 19
10.Find the value of −2x + 1 when x = 1
Answer: −1
- −2 × 1 + 1
- = −2 + 1 = −1
11.Find the value of −3x + 1 when x = 4
Answer: −11
- −3 × 4 + 1
- = −12 + 1 = −11
12.Find the value of 3x when x = 1
Answer: 3
- 3 × 1 + 0
- = 3 + 0 = 3
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