Year 9 Substitution Worksheet — Level 3 — 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 3 — Practice Set 3 — Answers
Replace the letter with the number, then calculate. Use brackets for negative values.
1.Find the value of x − 8 when x = 8
Answer: 0
- 1 × 8 − 8
- = 8 − 8 = 0
2.If x = −2 and y = 5, find the value of 9x2 + 0
Answer: 36
- 9 × (−2)² + 0 × (5)
- = 36 + 0 = 36
3.If x = −1 and y = 1, find the value of 4x2 − 3y
Answer: 1
- 4 × (−1)² − 3 × (1)
- = 4 − 3 = 1
4.If x = 7 and y = 3, find the value of 4x2 + 9y
Answer: 223
- 4 × (7)² + 9 × (3)
- = 196 + 27 = 223
5.If x = 2 and y = 6, find the value of 5x2 + 2y
Answer: 32
- 5 × (2)² + 2 × (6)
- = 20 + 12 = 32
6.If x = 9 and y = −1, find the value of 3x2 − 8y
Answer: 251
- 3 × (9)² − 8 × (−1)
- = 243 + 8 = 251
7.Find the value of 7x − 3 when x = −4
Answer: −31
- 7 × (−4) − 3
- = −28 − 3 = −31
8.Find the value of −x + 8 when x = 2
Answer: 6
- −1 × 2 + 8
- = −2 + 8 = 6
9.Find the value of 6x − 7 when x = −4
Answer: −31
- 6 × (−4) − 7
- = −24 − 7 = −31
10.Find the value of −4x + 9 when x = 4
Answer: −7
- −4 × 4 + 9
- = −16 + 9 = −7
11.If x = 5 and y = −4, find the value of 9x2 + 5y
Answer: 205
- 9 × (5)² + 5 × (−4)
- = 225 − 20 = 205
12.Find the value of 3x − 1 when x = 9
Answer: 26
- 3 × 9 − 1
- = 27 − 1 = 26
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