Year 9 Substitution Worksheet — Level 3 — Practice Set 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 — Practice Set 3 — Answers
Replace the letter with the number, then calculate. Use brackets for negative values.
1.If x = −1 and y = 2, find the value of 6x2 + 4y
Answer: 14
- 6 × (−1)² + 4 × (2)
- = 6 + 8 = 14
2.If x = 8 and y = −1, find the value of −x2 + 5y
Answer: −69
- −1 × (8)² + 5 × (−1)
- = −64 − 5 = −69
3.If x = 8 and y = −1, find the value of 3x2 + 7y
Answer: 185
- 3 × (8)² + 7 × (−1)
- = 192 − 7 = 185
4.Find the value of −3x − 1 when x = 9
Answer: −28
- −3 × 9 − 1
- = −27 − 1 = −28
5.If x = 1 and y = −4, find the value of −4x2 + 2y
Answer: −12
- −4 × (1)² + 2 × (−4)
- = −4 − 8 = −12
6.Find the value of 8x − 3 when x = −6
Answer: −51
- 8 × (−6) − 3
- = −48 − 3 = −51
7.If x = −6 and y = −4, find the value of −2x2 + 4y
Answer: −88
- −2 × (−6)² + 4 × (−4)
- = −72 − 16 = −88
8.Find the value of −x + 8 when x = 5
Answer: 3
- −1 × 5 + 8
- = −5 + 8 = 3
9.If x = −6 and y = 6, find the value of 4x2 − 7y
Answer: 102
- 4 × (−6)² − 7 × (6)
- = 144 − 42 = 102
10.Find the value of −2x + 5 when x = 3
Answer: −1
- −2 × 3 + 5
- = −6 + 5 = −1
11.Find the value of −4x + 3 when x = 3
Answer: −9
- −4 × 3 + 3
- = −12 + 3 = −9
12.If x = −4 and y = −4, find the value of −x2 − 5y
Answer: 4
- −1 × (−4)² − 5 × (−4)
- = −16 + 20 = 4
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