Year 8 Substitution Worksheet — Level 3 — Practice Set 4 — Answers
Answer sheet with worked solutions for the Year 8 algebraic expressions worksheet.
Success TutoringWorksheetsAnswer sheetYear 8 · Mathematics · Algebraic ExpressionsYear 8 Substitution Worksheet — Level 3 — Practice Set 4 — Answers
Replace the letter with the number, then calculate. Use brackets for negative values.
1.Find the value of −4x + 2 when x = 3
Answer: −10
- −4 × 3 + 2
- = −12 + 2 = −10
2.If x = −3 and y = 3, find the value of x2 + 0
Answer: 9
- 1 × (−3)² + 0 × (3)
- = 9 + 0 = 9
3.Find the value of 7x − 6 when x = 1
Answer: 1
- 7 × 1 − 6
- = 7 − 6 = 1
4.Find the value of 5x − 5 when x = 3
Answer: 10
- 5 × 3 − 5
- = 15 − 5 = 10
5.If x = 9 and y = 6, find the value of 8x2 − 9y
Answer: 594
- 8 × (9)² − 9 × (6)
- = 648 − 54 = 594
6.If x = −2 and y = 2, find the value of −x2 + 8y
Answer: 12
- −1 × (−2)² + 8 × (2)
- = −4 + 16 = 12
7.Find the value of −2x when x = 4
Answer: −8
- −2 × 4 + 0
- = −8 + 0 = −8
8.Find the value of 5x + 3 when x = 3
Answer: 18
- 5 × 3 + 3
- = 15 + 3 = 18
9.If x = 1 and y = −3, find the value of 6x2 − 2y
Answer: 12
- 6 × (1)² − 2 × (−3)
- = 6 + 6 = 12
10.Find the value of 2x + 9 when x = −4
Answer: 1
- 2 × (−4) + 9
- = −8 + 9 = 1
11.If x = 4 and y = 5, find the value of −5x2 + y
Answer: −75
- −5 × (4)² + 1 × (5)
- = −80 + 5 = −75
12.Find the value of 6x − 6 when x = 9
Answer: 48
- 6 × 9 − 6
- = 54 − 6 = 48
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