Year 8 Substitution Worksheet — Level 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 3 — Answers
Replace the letter with the number, then calculate. Use brackets for negative values.
1.If x = 3 and y = −1, find the value of 4x2 + y
Answer: 35
- 4 × (3)² + 1 × (−1)
- = 36 − 1 = 35
2.If x = −3 and y = 4, find the value of −3x2 + 9y
Answer: 9
- −3 × (−3)² + 9 × (4)
- = −27 + 36 = 9
3.If x = −1 and y = 3, find the value of 5x2 + 8y
Answer: 29
- 5 × (−1)² + 8 × (3)
- = 5 + 24 = 29
4.If x = −3 and y = −3, find the value of 3x2 + y
Answer: 24
- 3 × (−3)² + 1 × (−3)
- = 27 − 3 = 24
5.Find the value of 9x when x = 2
Answer: 18
- 9 × 2 + 0
- = 18 + 0 = 18
6.Find the value of −4x − 8 when x = −6
Answer: 16
- −4 × (−6) − 8
- = 24 − 8 = 16
7.If x = 3 and y = 2, find the value of 7x2 − 5y
Answer: 53
- 7 × (3)² − 5 × (2)
- = 63 − 10 = 53
8.If x = −5 and y = −2, find the value of −2x2 + 3y
Answer: −56
- −2 × (−5)² + 3 × (−2)
- = −50 − 6 = −56
9.If x = 8 and y = 5, find the value of 4x2 + 5y
Answer: 281
- 4 × (8)² + 5 × (5)
- = 256 + 25 = 281
10.Find the value of 9x + 1 when x = −6
Answer: −53
- 9 × (−6) + 1
- = −54 + 1 = −53
11.If x = −6 and y = 1, find the value of −5x2 + 7y
Answer: −173
- −5 × (−6)² + 7 × (1)
- = −180 + 7 = −173
12.Find the value of 7x − 3 when x = −6
Answer: −45
- 7 × (−6) − 3
- = −42 − 3 = −45
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