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

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

Download answers PDF Print answers Back to worksheet

Success TutoringWorksheetsAnswer sheet8th Grade · Mathematics · Algebraic Expressions

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

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

1.Simplify: −3x + 6y + 7x + 4y

Answer: 4x + 10y

x terms: −3x + 7x = 4x
y terms: 6y + 4y = 10y

2.Simplify: 9x + 5y − 3x + y

Answer: 6x + 6y

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

3.Simplify: −4x + 8y² + 8x + 8y²

Answer: 4x + 16y²

x terms: −4x + 8x = 4x
y² terms: 8y² + 8y² = 16y²

4.Simplify: −x + 7y² − 5x + 4y²

Answer: −6x + 11y²

x terms: −x − 5x = −6x
y² terms: 7y² + 4y² = 11y²

5.Simplify: 4x − y + 2x + 7y

Answer: 6x + 6y

x terms: 4x + 2x = 6x
y terms: −y + 7y = 6y

6.Simplify: −4x − 6y² − 2x + y²

Answer: −6x − 5y²

x terms: −4x − 2x = −6x
y² terms: −6y² + y² = −5y²

7.Simplify: −2x − 4y² + 6x + y²

Answer: 4x − 3y²

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

8.Simplify: −2x − 5y² − 6x + 9y²

Answer: −8x + 4y²

x terms: −2x − 6x = −8x
y² terms: −5y² + 9y² = 4y²

9.Simplify: 6x − 6y − 3x − 6y

Answer: 3x − 12y

x terms: 6x − 3x = 3x
y terms: −6y − 6y = −12y

10.Simplify: 8x + 8y + 4x + 3y

Answer: 12x + 11y

x terms: 8x + 4x = 12x
y terms: 8y + 3y = 11y

11.Simplify: −x + 5y − 5x + 5y

Answer: −6x + 10y

x terms: −x − 5x = −6x
y terms: 5y + 5y = 10y

12.Simplify: 5x + 6y² + 2x + 5y²

Answer: 7x + 11y²

x terms: 5x + 2x = 7x
y² terms: 6y² + 5y² = 11y²

13.Simplify: −3x + 5y + 5x + 4y

Answer: 2x + 9y

x terms: −3x + 5x = 2x
y terms: 5y + 4y = 9y

14.Simplify: −5x + 7y − 3x + 8y

Answer: −8x + 15y

x terms: −5x − 3x = −8x
y terms: 7y + 8y = 15y

Marking tips

Give credit for correct method even when the final answer slips — the working shows where the thinking went right.
For open-ended tasks, use the success criteria as a checklist rather than looking for one "right" answer.
Celebrate what went well first, then pick one thing to work on next.

Great work. Here's what to try next: