Year 8 Substitution Worksheet — Level 3 — Practice Set 2 — 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 — Practice Set 2 — Answers
Replace the letter with the number, then calculate. Use brackets for negative values.
1.If x = 3 and y = 3, find the value of 8x2 − 5y
Answer: 57
- 8 × (3)² − 5 × (3)
- = 72 − 15 = 57
2.If x = −2 and y = −1, find the value of −3x2 + 9y
Answer: −21
- −3 × (−2)² + 9 × (−1)
- = −12 − 9 = −21
3.If x = 6 and y = 3, find the value of 6x2 + 2y
Answer: 222
- 6 × (6)² + 2 × (3)
- = 216 + 6 = 222
4.Find the value of 8x − 6 when x = −1
Answer: −14
- 8 × (−1) − 6
- = −8 − 6 = −14
5.If x = −2 and y = 3, find the value of 5x2 − 3y
Answer: 11
- 5 × (−2)² − 3 × (3)
- = 20 − 9 = 11
6.Find the value of 3x + 2 when x = 4
Answer: 14
- 3 × 4 + 2
- = 12 + 2 = 14
7.Find the value of −3x − 6 when x = −4
Answer: 6
- −3 × (−4) − 6
- = 12 − 6 = 6
8.If x = −4 and y = 1, find the value of 9x2 + 6y
Answer: 150
- 9 × (−4)² + 6 × (1)
- = 144 + 6 = 150
9.Find the value of 6x − 9 when x = −1
Answer: −15
- 6 × (−1) − 9
- = −6 − 9 = −15
10.If x = 1 and y = 1, find the value of 7x2 + 4y
Answer: 11
- 7 × (1)² + 4 × (1)
- = 7 + 4 = 11
11.If x = 2 and y = −5, find the value of x2 − 5y
Answer: 29
- 1 × (2)² − 5 × (−5)
- = 4 + 25 = 29
12.If x = 4 and y = −3, find the value of −4x2 + 0
Answer: −64
- −4 × (4)² + 0 × (−3)
- = −64 + 0 = −64
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