7th Grade Substitution Worksheet — Level 3 — Answers
Answer sheet with worked solutions for the 7th Grade algebraic expressions worksheet.
Success TutoringWorksheetsAnswer sheet7th Grade · Mathematics · Algebraic Expressions7th Grade Substitution Worksheet — Level 3 — Answers
Replace the letter with the number, then calculate. Use parentheses for negative values.
1.If x = 1 and y = 6, find the value of 6x2 + 8y
Answer: 54
- 6 × (1)² + 8 × (6)
- = 6 + 48 = 54
2.If x = 9 and y = 2, find the value of 2x2 + 3y
Answer: 168
- 2 × (9)² + 3 × (2)
- = 162 + 6 = 168
3.Find the value of 7x when x = 1
Answer: 7
- 7 × 1 + 0
- = 7 + 0 = 7
4.Find the value of 2x − 7 when x = 2
Answer: −3
- 2 × 2 − 7
- = 4 − 7 = −3
5.If x = 7 and y = −4, find the value of 6x2 + 3y
Answer: 282
- 6 × (7)² + 3 × (−4)
- = 294 − 12 = 282
6.If x = 9 and y = −2, find the value of 7x2 − 3y
Answer: 573
- 7 × (9)² − 3 × (−2)
- = 567 + 6 = 573
7.If x = −5 and y = 5, find the value of −2x2 + 9y
Answer: −5
- −2 × (−5)² + 9 × (5)
- = −50 + 45 = −5
8.Find the value of x − 5 when x = 2
Answer: −3
- 1 × 2 − 5
- = 2 − 5 = −3
9.If x = 1 and y = 2, find the value of 7x2 + 4y
Answer: 15
- 7 × (1)² + 4 × (2)
- = 7 + 8 = 15
10.If x = −6 and y = −2, find the value of −5x2 + 6y
Answer: −192
- −5 × (−6)² + 6 × (−2)
- = −180 − 12 = −192
11.If x = 3 and y = 1, find the value of 3x2 − 4y
Answer: 23
- 3 × (3)² − 4 × (1)
- = 27 − 4 = 23
12.Find the value of 3x − 6 when x = −1
Answer: −9
- 3 × (−1) − 6
- = −3 − 6 = −9
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