7th Grade Substitution Worksheet — Level 3 — Practice Set 4 — Answers
Answer sheet with worked solutions for the 7th Grade algebraic expressions worksheet.
Success TutoringWorksheetsAnswer sheet7th Grade · Mathematics · Algebraic Expressions7th Grade Substitution Worksheet — Level 3 — Practice Set 4 — Answers
Replace the letter with the number, then calculate. Use parentheses for negative values.
1.If x = 6 and y = 6, find the value of 4x2 + 0
Answer: 144
- 4 × (6)² + 0 × (6)
- = 144 + 0 = 144
2.If x = 3 and y = −2, find the value of x2 + 8y
Answer: −7
- 1 × (3)² + 8 × (−2)
- = 9 − 16 = −7
3.If x = 2 and y = 4, find the value of 7x2 + 2y
Answer: 36
- 7 × (2)² + 2 × (4)
- = 28 + 8 = 36
4.If x = 2 and y = −3, find the value of −2x2 + 2y
Answer: −14
- −2 × (2)² + 2 × (−3)
- = −8 − 6 = −14
5.If x = 4 and y = −1, find the value of 7x2 − 4y
Answer: 116
- 7 × (4)² − 4 × (−1)
- = 112 + 4 = 116
6.Find the value of −2x + 9 when x = −4
Answer: 17
- −2 × (−4) + 9
- = 8 + 9 = 17
7.Find the value of −5x + 7 when x = 6
Answer: −23
- −5 × 6 + 7
- = −30 + 7 = −23
8.If x = 4 and y = 3, find the value of −3x2 − 2y
Answer: −54
- −3 × (4)² − 2 × (3)
- = −48 − 6 = −54
9.If x = −1 and y = 2, find the value of 6x2 − 5y
Answer: −4
- 6 × (−1)² − 5 × (2)
- = 6 − 10 = −4
10.If x = −6 and y = −1, find the value of 2x2 − 5y
Answer: 77
- 2 × (−6)² − 5 × (−1)
- = 72 + 5 = 77
11.Find the value of −x + 6 when x = −5
Answer: 11
- −1 × (−5) + 6
- = 5 + 6 = 11
12.Find the value of −2x + 3 when x = −2
Answer: 7
- −2 × (−2) + 3
- = 4 + 3 = 7
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