8th Grade Substitution Worksheet — Level 1 — Practice Set 2 — 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 2 — Answers
Replace the letter with the number, then calculate. Use parentheses for negative values.
1.Find the value of 3x − 5 when x = 6
Answer: 13
- 3 × 6 − 5
- = 18 − 5 = 13
2.Find the value of −3x + 9 when x = 8
Answer: −15
- −3 × 8 + 9
- = −24 + 9 = −15
3.Find the value of −4x − 4 when x = 6
Answer: −28
- −4 × 6 − 4
- = −24 − 4 = −28
4.Find the value of 9x + 7 when x = 7
Answer: 70
- 9 × 7 + 7
- = 63 + 7 = 70
5.Find the value of −3x − 6 when x = 9
Answer: −33
- −3 × 9 − 6
- = −27 − 6 = −33
6.Find the value of 2x − 2 when x = 3
Answer: 4
- 2 × 3 − 2
- = 6 − 2 = 4
7.Find the value of x − 4 when x = 6
Answer: 2
- 1 × 6 − 4
- = 6 − 4 = 2
8.Find the value of −3x − 6 when x = 4
Answer: −18
- −3 × 4 − 6
- = −12 − 6 = −18
9.Find the value of −x + 4 when x = 4
Answer: 0
- −1 × 4 + 4
- = −4 + 4 = 0
10.Find the value of 7x + 4 when x = 8
Answer: 60
- 7 × 8 + 4
- = 56 + 4 = 60
11.Find the value of −4x + 2 when x = 8
Answer: −30
- −4 × 8 + 2
- = −32 + 2 = −30
12.Find the value of −4x − 7 when x = 1
Answer: −11
- −4 × 1 − 7
- = −4 − 7 = −11
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