Year 9 Substitution Worksheet — Level 3 — Practice Set 4 — 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 4 — Answers
Replace the letter with the number, then calculate. Use brackets for negative values.
1.If x = 8 and y = −3, find the value of −4x2 + 0
Answer: −256
- −4 × (8)² + 0 × (−3)
- = −256 + 0 = −256
2.If x = 6 and y = −4, find the value of −4x2 + 6y
Answer: −168
- −4 × (6)² + 6 × (−4)
- = −144 − 24 = −168
3.If x = −5 and y = 1, find the value of 2x2 − 4y
Answer: 46
- 2 × (−5)² − 4 × (1)
- = 50 − 4 = 46
4.Find the value of 3x − 9 when x = 6
Answer: 9
- 3 × 6 − 9
- = 18 − 9 = 9
5.If x = 4 and y = 2, find the value of −5x2 + 2y
Answer: −76
- −5 × (4)² + 2 × (2)
- = −80 + 4 = −76
6.If x = 2 and y = −3, find the value of 3x2 − 7y
Answer: 33
- 3 × (2)² − 7 × (−3)
- = 12 + 21 = 33
7.If x = −3 and y = 1, find the value of 2x2 + 9y
Answer: 27
- 2 × (−3)² + 9 × (1)
- = 18 + 9 = 27
8.Find the value of −2x − 4 when x = 5
Answer: −14
- −2 × 5 − 4
- = −10 − 4 = −14
9.Find the value of −2x − 4 when x = −4
Answer: 4
- −2 × (−4) − 4
- = 8 − 4 = 4
10.If x = 7 and y = 3, find the value of −2x2 + 3y
Answer: −89
- −2 × (7)² + 3 × (3)
- = −98 + 9 = −89
11.If x = 5 and y = −2, find the value of −5x2 + y
Answer: −127
- −5 × (5)² + 1 × (−2)
- = −125 − 2 = −127
12.If x = −6 and y = 3, find the value of 4x2 + 6y
Answer: 162
- 4 × (−6)² + 6 × (3)
- = 144 + 18 = 162
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