8th Grade Substitution Worksheet — Level 1 — Practice Set 4 — 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 4 — Answers
Replace the letter with the number, then calculate. Use parentheses for negative values.
1.Find the value of 4x + 2 when x = 4
Answer: 18
- 4 × 4 + 2
- = 16 + 2 = 18
2.Find the value of 4x + 3 when x = 8
Answer: 35
- 4 × 8 + 3
- = 32 + 3 = 35
3.Find the value of 2x + 9 when x = 1
Answer: 11
- 2 × 1 + 9
- = 2 + 9 = 11
4.Find the value of −4x − 1 when x = 6
Answer: −25
- −4 × 6 − 1
- = −24 − 1 = −25
5.Find the value of 4x − 2 when x = 2
Answer: 6
- 4 × 2 − 2
- = 8 − 2 = 6
6.Find the value of 5x + 5 when x = 4
Answer: 25
- 5 × 4 + 5
- = 20 + 5 = 25
7.Find the value of 5x − 4 when x = 8
Answer: 36
- 5 × 8 − 4
- = 40 − 4 = 36
8.Find the value of −2x − 6 when x = 4
Answer: −14
- −2 × 4 − 6
- = −8 − 6 = −14
9.Find the value of −5x − 1 when x = 3
Answer: −16
- −5 × 3 − 1
- = −15 − 1 = −16
10.Find the value of 5x + 6 when x = 5
Answer: 31
- 5 × 5 + 6
- = 25 + 6 = 31
11.Find the value of −5x + 5 when x = 3
Answer: −10
- −5 × 3 + 5
- = −15 + 5 = −10
12.Find the value of x + 6 when x = 4
Answer: 10
- 1 × 4 + 6
- = 4 + 6 = 10
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