8th Grade Substitution Worksheet — Level 1 — 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 — Answers
Replace the letter with the number, then calculate. Use parentheses for negative values.
1.Find the value of −4x + 4 when x = 6
Answer: −20
- −4 × 6 + 4
- = −24 + 4 = −20
2.Find the value of 2x + 4 when x = 8
Answer: 20
- 2 × 8 + 4
- = 16 + 4 = 20
3.Find the value of 2x − 6 when x = 7
Answer: 8
- 2 × 7 − 6
- = 14 − 6 = 8
4.Find the value of 9x − 7 when x = 4
Answer: 29
- 9 × 4 − 7
- = 36 − 7 = 29
5.Find the value of 6x + 8 when x = 3
Answer: 26
- 6 × 3 + 8
- = 18 + 8 = 26
6.Find the value of −4x − 3 when x = 5
Answer: −23
- −4 × 5 − 3
- = −20 − 3 = −23
7.Find the value of 5x − 5 when x = 9
Answer: 40
- 5 × 9 − 5
- = 45 − 5 = 40
8.Find the value of 8x − 4 when x = 8
Answer: 60
- 8 × 8 − 4
- = 64 − 4 = 60
9.Find the value of 3x + 9 when x = 8
Answer: 33
- 3 × 8 + 9
- = 24 + 9 = 33
10.Find the value of 3x − 2 when x = 1
Answer: 1
- 3 × 1 − 2
- = 3 − 2 = 1
11.Find the value of 5x + 2 when x = 2
Answer: 12
- 5 × 2 + 2
- = 10 + 2 = 12
12.Find the value of −4x − 6 when x = 1
Answer: −10
- −4 × 1 − 6
- = −4 − 6 = −10
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