Year 9 Substitution Worksheet — Level 3 — Answers
Answer sheet with worked solutions for the Year 9 algebraic expressions worksheet.
Success TutoringWorksheetsAnswer sheetYear 9 · Mathematics · Algebraic ExpressionsYear 9 Substitution Worksheet — Level 3 — Answers
Replace the letter with the number, then calculate. Use brackets for negative values.
1.If x = 7 and y = −2, find the value of −x2 + 5y
Answer: −59
- −1 × (7)² + 5 × (−2)
- = −49 − 10 = −59
2.Find the value of 4x + 9 when x = −6
Answer: −15
- 4 × (−6) + 9
- = −24 + 9 = −15
3.If x = 6 and y = −3, find the value of −x2 − y
Answer: −33
- −1 × (6)² − 1 × (−3)
- = −36 + 3 = −33
4.If x = −3 and y = −2, find the value of 5x2 + 0
Answer: 45
- 5 × (−3)² + 0 × (−2)
- = 45 + 0 = 45
5.If x = 6 and y = 4, find the value of 7x2 + 0
Answer: 252
- 7 × (6)² + 0 × (4)
- = 252 + 0 = 252
6.If x = 8 and y = 6, find the value of x2 − 4y
Answer: 40
- 1 × (8)² − 4 × (6)
- = 64 − 24 = 40
7.Find the value of 2x − 6 when x = −1
Answer: −8
- 2 × (−1) − 6
- = −2 − 6 = −8
8.If x = −2 and y = 1, find the value of −2x2 − y
Answer: −9
- −2 × (−2)² − 1 × (1)
- = −8 − 1 = −9
9.Find the value of 8x − 7 when x = 5
Answer: 33
- 8 × 5 − 7
- = 40 − 7 = 33
10.If x = −6 and y = 3, find the value of x2 − y
Answer: 33
- 1 × (−6)² − 1 × (3)
- = 36 − 3 = 33
11.If x = 6 and y = 2, find the value of −3x2 − 4y
Answer: −116
- −3 × (6)² − 4 × (2)
- = −108 − 8 = −116
12.Find the value of −x + 4 when x = 6
Answer: −2
- −1 × 6 + 4
- = −6 + 4 = −2
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