7th Grade Substitution Worksheet — Level 3 — Practice Set 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 — Practice Set 3 — Answers
Replace the letter with the number, then calculate. Use parentheses for negative values.
1.Find the value of 9x − 4 when x = −6
Answer: −58
- 9 × (−6) − 4
- = −54 − 4 = −58
2.If x = 9 and y = 3, find the value of 6x2 − 3y
Answer: 477
- 6 × (9)² − 3 × (3)
- = 486 − 9 = 477
3.Find the value of 7x + 1 when x = 2
Answer: 15
- 7 × 2 + 1
- = 14 + 1 = 15
4.Find the value of −4x + 2 when x = −5
Answer: 22
- −4 × (−5) + 2
- = 20 + 2 = 22
5.Find the value of 7x + 2 when x = −5
Answer: −33
- 7 × (−5) + 2
- = −35 + 2 = −33
6.Find the value of 6x − 7 when x = −5
Answer: −37
- 6 × (−5) − 7
- = −30 − 7 = −37
7.If x = 8 and y = −3, find the value of −5x2 + 5y
Answer: −335
- −5 × (8)² + 5 × (−3)
- = −320 − 15 = −335
8.Find the value of −x + 5 when x = 1
Answer: 4
- −1 × 1 + 5
- = −1 + 5 = 4
9.Find the value of 4x − 7 when x = 6
Answer: 17
- 4 × 6 − 7
- = 24 − 7 = 17
10.If x = 3 and y = 1, find the value of −4x2 − y
Answer: −37
- −4 × (3)² − 1 × (1)
- = −36 − 1 = −37
11.Find the value of −4x + 5 when x = −5
Answer: 25
- −4 × (−5) + 5
- = 20 + 5 = 25
12.Find the value of −4x − 8 when x = −6
Answer: 16
- −4 × (−6) − 8
- = 24 − 8 = 16
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