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.If x = 9 and y = 5, find the value of −2x2 + 6y
Answer: −132
- −2 × (9)² + 6 × (5)
- = −162 + 30 = −132
2.Find the value of 8x − 2 when x = 4
Answer: 30
- 8 × 4 − 2
- = 32 − 2 = 30
3.Find the value of 2x + 4 when x = 3
Answer: 10
- 2 × 3 + 4
- = 6 + 4 = 10
4.Find the value of −2x + 1 when x = 2
Answer: −3
- −2 × 2 + 1
- = −4 + 1 = −3
5.Find the value of 6x − 6 when x = 3
Answer: 12
- 6 × 3 − 6
- = 18 − 6 = 12
6.Find the value of x + 9 when x = −6
Answer: 3
- 1 × (−6) + 9
- = −6 + 9 = 3
7.If x = −5 and y = 6, find the value of 8x2 + 5y
Answer: 230
- 8 × (−5)² + 5 × (6)
- = 200 + 30 = 230
8.If x = 9 and y = 3, find the value of 7x2 + 2y
Answer: 573
- 7 × (9)² + 2 × (3)
- = 567 + 6 = 573
9.Find the value of 2x + 4 when x = −1
Answer: 2
- 2 × (−1) + 4
- = −2 + 4 = 2
10.Find the value of 3x − 7 when x = 3
Answer: 2
- 3 × 3 − 7
- = 9 − 7 = 2
11.Find the value of −5x − 3 when x = −3
Answer: 12
- −5 × (−3) − 3
- = 15 − 3 = 12
12.Find the value of 3x + 9 when x = 3
Answer: 18
- 3 × 3 + 9
- = 9 + 9 = 18
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