8th Grade Substitution Worksheet — Level 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 2 — Answers
Replace the letter with the number, then calculate. Use parentheses for negative values.
1.Find the value of 4x + 5 when x = −4
Answer: −11
- 4 × (−4) + 5
- = −16 + 5 = −11
2.Find the value of 5x + 6 when x = −5
Answer: −19
- 5 × (−5) + 6
- = −25 + 6 = −19
3.Find the value of 4x − 8 when x = −1
Answer: −12
- 4 × (−1) − 8
- = −4 − 8 = −12
4.Find the value of −4x + 8 when x = 9
Answer: −28
- −4 × 9 + 8
- = −36 + 8 = −28
5.Find the value of 5x − 1 when x = −4
Answer: −21
- 5 × (−4) − 1
- = −20 − 1 = −21
6.Find the value of 9x + 6 when x = −1
Answer: −3
- 9 × (−1) + 6
- = −9 + 6 = −3
7.Find the value of 4x + 4 when x = 6
Answer: 28
- 4 × 6 + 4
- = 24 + 4 = 28
8.Find the value of 2x + 8 when x = −4
Answer: 0
- 2 × (−4) + 8
- = −8 + 8 = 0
9.Find the value of 7x when x = −3
Answer: −21
- 7 × (−3) + 0
- = −21 + 0 = −21
10.Find the value of −4x − 4 when x = −2
Answer: 4
- −4 × (−2) − 4
- = 8 − 4 = 4
11.Find the value of 9x − 1 when x = 8
Answer: 71
- 9 × 8 − 1
- = 72 − 1 = 71
12.Find the value of x + 7 when x = −2
Answer: 5
- 1 × (−2) + 7
- = −2 + 7 = 5
Marking tips
- Give credit for correct method even when the final answer slips — the working shows where the thinking went right.
- For open-ended tasks, use the success criteria as a checklist rather than looking for one "right" answer.
- Celebrate what went well first, then pick one thing to work on next.
Great work. Here's what to try next: