Year 7 Substitution Worksheet — Level 3 — Practice Set 2 — 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 2 — Answers
Replace the letter with the number, then calculate. Use brackets for negative values.
1.Find the value of 4x + 4 when x = −4
Answer: −12
- 4 × (−4) + 4
- = −16 + 4 = −12
2.Find the value of −3x + 7 when x = 8
Answer: −17
- −3 × 8 + 7
- = −24 + 7 = −17
3.If x = 2 and y = 2, find the value of 7x2 + 4y
Answer: 36
- 7 × (2)² + 4 × (2)
- = 28 + 8 = 36
4.Find the value of 4x + 7 when x = −3
Answer: −5
- 4 × (−3) + 7
- = −12 + 7 = −5
5.Find the value of 6x − 3 when x = −4
Answer: −27
- 6 × (−4) − 3
- = −24 − 3 = −27
6.Find the value of −5x + 3 when x = −6
Answer: 33
- −5 × (−6) + 3
- = 30 + 3 = 33
7.If x = −5 and y = −2, find the value of 2x2 + 6y
Answer: 38
- 2 × (−5)² + 6 × (−2)
- = 50 − 12 = 38
8.If x = −5 and y = 1, find the value of −2x2 + 9y
Answer: −41
- −2 × (−5)² + 9 × (1)
- = −50 + 9 = −41
9.If x = 8 and y = 2, find the value of −5x2 + 8y
Answer: −304
- −5 × (8)² + 8 × (2)
- = −320 + 16 = −304
10.Find the value of −4x + 2 when x = −6
Answer: 26
- −4 × (−6) + 2
- = 24 + 2 = 26
11.Find the value of 9x + 3 when x = 6
Answer: 57
- 9 × 6 + 3
- = 54 + 3 = 57
12.If x = 1 and y = 1, find the value of 9x2 + 5y
Answer: 14
- 9 × (1)² + 5 × (1)
- = 9 + 5 = 14
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