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.Find the value of −x + 7 when x = 9
Answer: −2
- −1 × 9 + 7
- = −9 + 7 = −2
2.Find the value of −5x + 5 when x = 7
Answer: −30
- −5 × 7 + 5
- = −35 + 5 = −30
3.If x = 4 and y = −2, find the value of −2x2 − 4y
Answer: −24
- −2 × (4)² − 4 × (−2)
- = −32 + 8 = −24
4.Find the value of 5x + 8 when x = 4
Answer: 28
- 5 × 4 + 8
- = 20 + 8 = 28
5.If x = 7 and y = 2, find the value of 3x2 − 8y
Answer: 131
- 3 × (7)² − 8 × (2)
- = 147 − 16 = 131
6.Find the value of −x − 1 when x = 3
Answer: −4
- −1 × 3 − 1
- = −3 − 1 = −4
7.Find the value of 4x + 9 when x = 4
Answer: 25
- 4 × 4 + 9
- = 16 + 9 = 25
8.If x = 3 and y = 5, find the value of 4x2 + 9y
Answer: 81
- 4 × (3)² + 9 × (5)
- = 36 + 45 = 81
9.If x = −1 and y = −4, find the value of 6x2 + y
Answer: 2
- 6 × (−1)² + 1 × (−4)
- = 6 − 4 = 2
10.If x = 8 and y = −2, find the value of 3x2 − 4y
Answer: 200
- 3 × (8)² − 4 × (−2)
- = 192 + 8 = 200
11.Find the value of 9x + 1 when x = −6
Answer: −53
- 9 × (−6) + 1
- = −54 + 1 = −53
12.Find the value of 9x − 3 when x = −3
Answer: −30
- 9 × (−3) − 3
- = −27 − 3 = −30
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