Year 9 Substitution Worksheet — Level 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 3 — Answers
Replace the letter with the number, then calculate. Use brackets for negative values.
1.Find the value of 3x + 2 when x = 4
Answer: 14
- 3 × 4 + 2
- = 12 + 2 = 14
2.Find the value of 5x − 4 when x = 4
Answer: 16
- 5 × 4 − 4
- = 20 − 4 = 16
3.Find the value of −x + 5 when x = −6
Answer: 11
- −1 × (−6) + 5
- = 6 + 5 = 11
4.If x = −6 and y = 1, find the value of 4x2 + 2y
Answer: 146
- 4 × (−6)² + 2 × (1)
- = 144 + 2 = 146
5.If x = 7 and y = 4, find the value of 3x2 + y
Answer: 151
- 3 × (7)² + 1 × (4)
- = 147 + 4 = 151
6.If x = 7 and y = −1, find the value of −2x2 − 7y
Answer: −91
- −2 × (7)² − 7 × (−1)
- = −98 + 7 = −91
7.If x = 8 and y = −2, find the value of −3x2 − 3y
Answer: −186
- −3 × (8)² − 3 × (−2)
- = −192 + 6 = −186
8.Find the value of 7x − 5 when x = −3
Answer: −26
- 7 × (−3) − 5
- = −21 − 5 = −26
9.If x = 4 and y = 3, find the value of −5x2 + 9y
Answer: −53
- −5 × (4)² + 9 × (3)
- = −80 + 27 = −53
10.Find the value of 9x + 5 when x = −3
Answer: −22
- 9 × (−3) + 5
- = −27 + 5 = −22
11.Find the value of 6x − 7 when x = 7
Answer: 35
- 6 × 7 − 7
- = 42 − 7 = 35
12.If x = 3 and y = 4, find the value of 9x2 − 6y
Answer: 57
- 9 × (3)² − 6 × (4)
- = 81 − 24 = 57
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