Year 7 Substitution Worksheet — Level 3 — Answers
Answer sheet with worked solutions for the Year 7 algebraic expressions worksheet.
Success TutoringWorksheetsAnswer sheetYear 7 · Mathematics · Algebraic ExpressionsYear 7 Substitution Worksheet — Level 3 — Answers
Replace the letter with the number, then calculate. Use brackets for negative values.
1.If x = −2 and y = −5, find the value of 8x2 − 4y
Answer: 52
- 8 × (−2)² − 4 × (−5)
- = 32 + 20 = 52
2.Find the value of 8x + 5 when x = 7
Answer: 61
- 8 × 7 + 5
- = 56 + 5 = 61
3.If x = −6 and y = 1, find the value of 5x2 − 7y
Answer: 173
- 5 × (−6)² − 7 × (1)
- = 180 − 7 = 173
4.If x = 5 and y = 6, find the value of 5x2 − 2y
Answer: 113
- 5 × (5)² − 2 × (6)
- = 125 − 12 = 113
5.Find the value of 2x + 3 when x = −1
Answer: 1
- 2 × (−1) + 3
- = −2 + 3 = 1
6.If x = −3 and y = −5, find the value of 8x2 − 8y
Answer: 112
- 8 × (−3)² − 8 × (−5)
- = 72 + 40 = 112
7.If x = −4 and y = 1, find the value of 5x2 − 9y
Answer: 71
- 5 × (−4)² − 9 × (1)
- = 80 − 9 = 71
8.Find the value of 9x − 6 when x = 2
Answer: 12
- 9 × 2 − 6
- = 18 − 6 = 12
9.Find the value of 6x + 2 when x = 3
Answer: 20
- 6 × 3 + 2
- = 18 + 2 = 20
10.Find the value of 7x + 8 when x = 7
Answer: 57
- 7 × 7 + 8
- = 49 + 8 = 57
11.Find the value of −2x − 9 when x = 8
Answer: −25
- −2 × 8 − 9
- = −16 − 9 = −25
12.If x = 7 and y = 3, find the value of −3x2 + 3y
Answer: −138
- −3 × (7)² + 3 × (3)
- = −147 + 9 = −138
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