Year 7 Substitution Worksheet — Level 3 — Practice Set 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 — Practice Set 3 — Answers
Replace the letter with the number, then calculate. Use brackets for negative values.
1.If x = −5 and y = −2, find the value of −4x2 − 7y
Answer: −86
- −4 × (−5)² − 7 × (−2)
- = −100 + 14 = −86
2.If x = −1 and y = 6, find the value of −3x2 + y
Answer: 3
- −3 × (−1)² + 1 × (6)
- = −3 + 6 = 3
3.Find the value of 6x − 1 when x = 7
Answer: 41
- 6 × 7 − 1
- = 42 − 1 = 41
4.Find the value of 7x + 3 when x = 6
Answer: 45
- 7 × 6 + 3
- = 42 + 3 = 45
5.Find the value of −3x + 6 when x = −2
Answer: 12
- −3 × (−2) + 6
- = 6 + 6 = 12
6.Find the value of 2x + 1 when x = −1
Answer: −1
- 2 × (−1) + 1
- = −2 + 1 = −1
7.If x = 4 and y = −5, find the value of 4x2 + 9y
Answer: 19
- 4 × (4)² + 9 × (−5)
- = 64 − 45 = 19
8.Find the value of 9x − 3 when x = 8
Answer: 69
- 9 × 8 − 3
- = 72 − 3 = 69
9.Find the value of 2x − 1 when x = 6
Answer: 11
- 2 × 6 − 1
- = 12 − 1 = 11
10.Find the value of 5x − 8 when x = 9
Answer: 37
- 5 × 9 − 8
- = 45 − 8 = 37
11.Find the value of −3x − 7 when x = −5
Answer: 8
- −3 × (−5) − 7
- = 15 − 7 = 8
12.Find the value of x + 6 when x = −1
Answer: 5
- 1 × (−1) + 6
- = −1 + 6 = 5
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