Year 9 Substitution Worksheet — Level 3 — Practice Set 2 — 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 — Practice Set 2 — Answers
Replace the letter with the number, then calculate. Use brackets for negative values.
1.If x = −2 and y = 3, find the value of −2x2 − 9y
Answer: −35
- −2 × (−2)² − 9 × (3)
- = −8 − 27 = −35
2.Find the value of x + 3 when x = −3
Answer: 0
- 1 × (−3) + 3
- = −3 + 3 = 0
3.If x = −4 and y = 2, find the value of −x2 + 4y
Answer: −8
- −1 × (−4)² + 4 × (2)
- = −16 + 8 = −8
4.Find the value of 9x − 6 when x = −1
Answer: −15
- 9 × (−1) − 6
- = −9 − 6 = −15
5.Find the value of 9x + 9 when x = −1
Answer: 0
- 9 × (−1) + 9
- = −9 + 9 = 0
6.If x = 9 and y = −5, find the value of 3x2 − 6y
Answer: 273
- 3 × (9)² − 6 × (−5)
- = 243 + 30 = 273
7.If x = 3 and y = −3, find the value of −2x2 + 6y
Answer: −36
- −2 × (3)² + 6 × (−3)
- = −18 − 18 = −36
8.If x = 3 and y = −3, find the value of 7x2 − 5y
Answer: 78
- 7 × (3)² − 5 × (−3)
- = 63 + 15 = 78
9.Find the value of x + 3 when x = 9
Answer: 12
- 1 × 9 + 3
- = 9 + 3 = 12
10.If x = −6 and y = −2, find the value of −3x2 + 4y
Answer: −116
- −3 × (−6)² + 4 × (−2)
- = −108 − 8 = −116
11.If x = 9 and y = 2, find the value of −3x2 − 6y
Answer: −255
- −3 × (9)² − 6 × (2)
- = −243 − 12 = −255
12.If x = −4 and y = −2, find the value of 3x2 − 2y
Answer: 52
- 3 × (−4)² − 2 × (−2)
- = 48 + 4 = 52
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