7th Grade Substitution Worksheet — Level 1 — 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 1 — Practice Set 3 — Answers
Replace the letter with the number, then calculate. Use parentheses for negative values.
1.Find the value of −4x − 7 when x = 8
Answer: −39
- −4 × 8 − 7
- = −32 − 7 = −39
2.Find the value of −x + 6 when x = 9
Answer: −3
- −1 × 9 + 6
- = −9 + 6 = −3
3.Find the value of 6x − 7 when x = 2
Answer: 5
- 6 × 2 − 7
- = 12 − 7 = 5
4.Find the value of 3x + 6 when x = 1
Answer: 9
- 3 × 1 + 6
- = 3 + 6 = 9
5.Find the value of 5x − 1 when x = 8
Answer: 39
- 5 × 8 − 1
- = 40 − 1 = 39
6.Find the value of 6x − 9 when x = 4
Answer: 15
- 6 × 4 − 9
- = 24 − 9 = 15
7.Find the value of x + 9 when x = 5
Answer: 14
- 1 × 5 + 9
- = 5 + 9 = 14
8.Find the value of −5x + 8 when x = 9
Answer: −37
- −5 × 9 + 8
- = −45 + 8 = −37
9.Find the value of 9x + 4 when x = 4
Answer: 40
- 9 × 4 + 4
- = 36 + 4 = 40
10.Find the value of −4x when x = 2
Answer: −8
- −4 × 2 + 0
- = −8 + 0 = −8
11.Find the value of −x + 6 when x = 8
Answer: −2
- −1 × 8 + 6
- = −8 + 6 = −2
12.Find the value of 9x + 6 when x = 8
Answer: 78
- 9 × 8 + 6
- = 72 + 6 = 78
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