8th Grade Substitution Worksheet — Level 2 — 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 2 — Practice Set 3 — Answers
Replace the letter with the number, then calculate. Use parentheses for negative values.
1.Find the value of 9x + 3 when x = −6
Answer: −51
- 9 × (−6) + 3
- = −54 + 3 = −51
2.Find the value of 8x − 5 when x = 2
Answer: 11
- 8 × 2 − 5
- = 16 − 5 = 11
3.Find the value of 6x + 4 when x = 7
Answer: 46
- 6 × 7 + 4
- = 42 + 4 = 46
4.Find the value of −x − 9 when x = 9
Answer: −18
- −1 × 9 − 9
- = −9 − 9 = −18
5.Find the value of 7x − 4 when x = 5
Answer: 31
- 7 × 5 − 4
- = 35 − 4 = 31
6.Find the value of −4x − 3 when x = 9
Answer: −39
- −4 × 9 − 3
- = −36 − 3 = −39
7.Find the value of −2x − 6 when x = 7
Answer: −20
- −2 × 7 − 6
- = −14 − 6 = −20
8.Find the value of 8x + 3 when x = 8
Answer: 67
- 8 × 8 + 3
- = 64 + 3 = 67
9.Find the value of −x − 5 when x = 5
Answer: −10
- −1 × 5 − 5
- = −5 − 5 = −10
10.Find the value of −4x − 2 when x = 5
Answer: −22
- −4 × 5 − 2
- = −20 − 2 = −22
11.Find the value of −2x − 4 when x = 3
Answer: −10
- −2 × 3 − 4
- = −6 − 4 = −10
12.Find the value of 8x + 1 when x = 5
Answer: 41
- 8 × 5 + 1
- = 40 + 1 = 41
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