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

Answer sheet with worked solutions for the Year 8 algebraic expressions worksheet.

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Year 8 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 − y + 9x − 4y

Answer: 12x − 5y

x terms: 3x + 9x = 12x
y terms: −y − 4y = −5y

2.Simplify: −x − 3y + 8x − 3y

Answer: 7x − 6y

x terms: −x + 8x = 7x
y terms: −3y − 3y = −6y

3.Simplify: −2x + 4y² − 6x − 3y²

Answer: −8x + y²

x terms: −2x − 6x = −8x
y² terms: 4y² − 3y² = y²

4.Simplify: 4x + 5y² − 4x − 6y²

Answer: −y²

x terms: 4x − 4x = 0
y² terms: 5y² − 6y² = −y²

5.Simplify: −x + 6y² − 4x + 9y²

Answer: −5x + 15y²

x terms: −x − 4x = −5x
y² terms: 6y² + 9y² = 15y²

6.Simplify: 9x − 5y − 6x + 4y

Answer: 3x − y

x terms: 9x − 6x = 3x
y terms: −5y + 4y = −y

7.Simplify: 6x − 4y + 3x − 5y

Answer: 9x − 9y

x terms: 6x + 3x = 9x
y terms: −4y − 5y = −9y

8.Simplify: −3x + y + 7x + 4y

Answer: 4x + 5y

x terms: −3x + 7x = 4x
y terms: y + 4y = 5y

9.Simplify: 6x + 2y² − 5x + 9y²

Answer: x + 11y²

x terms: 6x − 5x = x
y² terms: 2y² + 9y² = 11y²

10.Simplify: 3x + 7y + x + 3y

Answer: 4x + 10y

x terms: 3x + x = 4x
y terms: 7y + 3y = 10y

11.Simplify: 5x − 2y − 2x + 4y

Answer: 3x + 2y

x terms: 5x − 2x = 3x
y terms: −2y + 4y = 2y

12.Simplify: −3x + 7y² − 5x + y²

Answer: −8x + 8y²

x terms: −3x − 5x = −8x
y² terms: 7y² + y² = 8y²

13.Simplify: 3x + 9y + 6x + 4y

Answer: 9x + 13y

x terms: 3x + 6x = 9x
y terms: 9y + 4y = 13y

14.Simplify: −4x + 9y² − 3x − 2y²

Answer: −7x + 7y²

x terms: −4x − 3x = −7x
y² terms: 9y² − 2y² = 7y²

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