Year 9 Substitution Worksheet — Level 2 — Practice Set 3 — Answers
Answer sheet with worked solutions for the Year 9 algebraic expressions worksheet.
Success TutoringWorksheetsAnswer sheetYear 9 · Mathematics · Algebraic ExpressionsYear 9 Substitution Worksheet — Level 2 — Practice Set 3 — Answers
Replace the letter with the number, then calculate. Use brackets for negative values.
1.Find the value of 4x + 7 when x = 4
Answer: 23
- 4 × 4 + 7
- = 16 + 7 = 23
2.Find the value of 7x + 5 when x = 1
Answer: 12
- 7 × 1 + 5
- = 7 + 5 = 12
3.Find the value of 4x + 2 when x = 1
Answer: 6
- 4 × 1 + 2
- = 4 + 2 = 6
4.Find the value of 8x − 8 when x = −5
Answer: −48
- 8 × (−5) − 8
- = −40 − 8 = −48
5.Find the value of x + 5 when x = −1
Answer: 4
- 1 × (−1) + 5
- = −1 + 5 = 4
6.Find the value of 5x + 4 when x = 6
Answer: 34
- 5 × 6 + 4
- = 30 + 4 = 34
7.Find the value of −3x + 1 when x = 8
Answer: −23
- −3 × 8 + 1
- = −24 + 1 = −23
8.Find the value of −x − 6 when x = 7
Answer: −13
- −1 × 7 − 6
- = −7 − 6 = −13
9.Find the value of −5x − 5 when x = −1
Answer: 0
- −5 × (−1) − 5
- = 5 − 5 = 0
10.Find the value of −4x − 7 when x = −5
Answer: 13
- −4 × (−5) − 7
- = 20 − 7 = 13
11.Find the value of 3x − 6 when x = −3
Answer: −15
- 3 × (−3) − 6
- = −9 − 6 = −15
12.Find the value of 7x + 9 when x = −6
Answer: −33
- 7 × (−6) + 9
- = −42 + 9 = −33
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