9th Grade Substitution Worksheet — Level 1 — Practice Set 4 — Answers
Answer sheet with worked solutions for the 9th Grade algebraic expressions worksheet.
Success TutoringWorksheetsAnswer sheet9th Grade · Mathematics · Algebraic Expressions9th 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 3x + 8 when x = 6
Answer: 26
- 3 × 6 + 8
- = 18 + 8 = 26
2.Find the value of x − 6 when x = 9
Answer: 3
- 1 × 9 − 6
- = 9 − 6 = 3
3.Find the value of 3x + 4 when x = 1
Answer: 7
- 3 × 1 + 4
- = 3 + 4 = 7
4.Find the value of −x + 6 when x = 6
Answer: 0
- −1 × 6 + 6
- = −6 + 6 = 0
5.Find the value of 7x + 9 when x = 8
Answer: 65
- 7 × 8 + 9
- = 56 + 9 = 65
6.Find the value of −4x − 9 when x = 7
Answer: −37
- −4 × 7 − 9
- = −28 − 9 = −37
7.Find the value of 2x + 7 when x = 4
Answer: 15
- 2 × 4 + 7
- = 8 + 7 = 15
8.Find the value of 3x + 3 when x = 4
Answer: 15
- 3 × 4 + 3
- = 12 + 3 = 15
9.Find the value of −2x + 5 when x = 9
Answer: −13
- −2 × 9 + 5
- = −18 + 5 = −13
10.Find the value of −3x − 4 when x = 6
Answer: −22
- −3 × 6 − 4
- = −18 − 4 = −22
11.Find the value of 9x + 7 when x = 9
Answer: 88
- 9 × 9 + 7
- = 81 + 7 = 88
12.Find the value of 2x − 4 when x = 2
Answer: 0
- 2 × 2 − 4
- = 4 − 4 = 0
Marking tips
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