8th Grade Substitution Worksheet — Level 1 — Practice Set 3 — Answers
Answer sheet with worked solutions for the 8th Grade algebraic expressions worksheet.
Success TutoringWorksheetsAnswer sheet8th Grade · Mathematics · Algebraic Expressions8th 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 3x − 1 when x = 5
Answer: 14
- 3 × 5 − 1
- = 15 − 1 = 14
2.Find the value of 5x + 9 when x = 2
Answer: 19
- 5 × 2 + 9
- = 10 + 9 = 19
3.Find the value of −4x + 1 when x = 4
Answer: −15
- −4 × 4 + 1
- = −16 + 1 = −15
4.Find the value of 5x + 7 when x = 6
Answer: 37
- 5 × 6 + 7
- = 30 + 7 = 37
5.Find the value of 9x + 6 when x = 8
Answer: 78
- 9 × 8 + 6
- = 72 + 6 = 78
6.Find the value of −5x − 9 when x = 3
Answer: −24
- −5 × 3 − 9
- = −15 − 9 = −24
7.Find the value of 8x − 5 when x = 9
Answer: 67
- 8 × 9 − 5
- = 72 − 5 = 67
8.Find the value of −2x − 9 when x = 1
Answer: −11
- −2 × 1 − 9
- = −2 − 9 = −11
9.Find the value of −x + 9 when x = 4
Answer: 5
- −1 × 4 + 9
- = −4 + 9 = 5
10.Find the value of 5x − 1 when x = 6
Answer: 29
- 5 × 6 − 1
- = 30 − 1 = 29
11.Find the value of −2x − 7 when x = 9
Answer: −25
- −2 × 9 − 7
- = −18 − 7 = −25
12.Find the value of 8x − 2 when x = 2
Answer: 14
- 8 × 2 − 2
- = 16 − 2 = 14
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