8th Grade Simplifying Expressions (Like Terms) Worksheet — Level 3 — Practice Set 4 — Answers

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8th Grade Simplifying Expressions (Like Terms) Worksheet — Level 3 — Practice Set 4 — Answers

Collect the like terms. Only terms with exactly the same letter and power can be added.

1.Simplify: −3x − 5y + 5x + 5y

Answer: 2x

x terms: −3x + 5x = 2x
y terms: −5y + 5y = 0

2.Simplify: −4x + y + 2x − 2y

Answer: −2x − y

x terms: −4x + 2x = −2x
y terms: y − 2y = −y

3.Simplify: 2x − 4y − x + 9y

Answer: x + 5y

x terms: 2x − x = x
y terms: −4y + 9y = 5y

4.Simplify: 5x + 9y − 2x − 2y

Answer: 3x + 7y

x terms: 5x − 2x = 3x
y terms: 9y − 2y = 7y

5.Simplify: 3x + 2y² + 9x + 2y²

Answer: 12x + 4y²

x terms: 3x + 9x = 12x
y² terms: 2y² + 2y² = 4y²

6.Simplify: −3x − 3y² − 3x + 8y²

Answer: −6x + 5y²

x terms: −3x − 3x = −6x
y² terms: −3y² + 8y² = 5y²

7.Simplify: x + 4y² + x + y²

Answer: 2x + 5y²

x terms: x + x = 2x
y² terms: 4y² + y² = 5y²

8.Simplify: x + 4y − 4x + 9y

Answer: −3x + 13y

x terms: x − 4x = −3x
y terms: 4y + 9y = 13y

9.Simplify: −2x − y + 4x + 3y

Answer: 2x + 2y

x terms: −2x + 4x = 2x
y terms: −y + 3y = 2y

10.Simplify: −6x + 4y² − 2x + 4y²

Answer: −8x + 8y²

x terms: −6x − 2x = −8x
y² terms: 4y² + 4y² = 8y²

11.Simplify: −2x + 7y² + 5x − 4y²

Answer: 3x + 3y²

x terms: −2x + 5x = 3x
y² terms: 7y² − 4y² = 3y²

12.Simplify: −2x − y + 4x + 2y

Answer: 2x + y

x terms: −2x + 4x = 2x
y terms: −y + 2y = y

13.Simplify: −2x − 2y² − 2x + 2y²

Answer: −4x

x terms: −2x − 2x = −4x
y² terms: −2y² + 2y² = 0

14.Simplify: 9x − 3y² + 9x + 8y²

Answer: 18x + 5y²

x terms: 9x + 9x = 18x
y² terms: −3y² + 8y² = 5y²

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