Year 8 Substitution Worksheet — Level 3 — Answers
Answer sheet with worked solutions for the Year 8 algebraic expressions worksheet.
Success TutoringWorksheetsAnswer sheetYear 8 · Mathematics · Algebraic ExpressionsYear 8 Substitution Worksheet — Level 3 — Answers
Replace the letter with the number, then calculate. Use brackets for negative values.
1.Find the value of −5x when x = −4
Answer: 20
- −5 × (−4) + 0
- = 20 + 0 = 20
2.Find the value of 5x + 3 when x = 7
Answer: 38
- 5 × 7 + 3
- = 35 + 3 = 38
3.If x = −6 and y = −2, find the value of 4x2 − 2y
Answer: 148
- 4 × (−6)² − 2 × (−2)
- = 144 + 4 = 148
4.If x = 3 and y = −3, find the value of −3x2 + 4y
Answer: −39
- −3 × (3)² + 4 × (−3)
- = −27 − 12 = −39
5.If x = 5 and y = 6, find the value of 9x2 + 7y
Answer: 267
- 9 × (5)² + 7 × (6)
- = 225 + 42 = 267
6.If x = −6 and y = 4, find the value of 6x2 + 2y
Answer: 224
- 6 × (−6)² + 2 × (4)
- = 216 + 8 = 224
7.Find the value of 8x − 1 when x = 7
Answer: 55
- 8 × 7 − 1
- = 56 − 1 = 55
8.Find the value of 8x − 5 when x = −5
Answer: −45
- 8 × (−5) − 5
- = −40 − 5 = −45
9.If x = 8 and y = −4, find the value of 5x2 − 7y
Answer: 348
- 5 × (8)² − 7 × (−4)
- = 320 + 28 = 348
10.Find the value of −x − 6 when x = −6
Answer: 0
- −1 × (−6) − 6
- = 6 − 6 = 0
11.Find the value of 5x − 4 when x = 4
Answer: 16
- 5 × 4 − 4
- = 20 − 4 = 16
12.If x = −2 and y = 3, find the value of 4x2 + 2y
Answer: 22
- 4 × (−2)² + 2 × (3)
- = 16 + 6 = 22
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