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# Adding and subtracting polynomials with two variables review

Adding and subtracting polynomials is all about combining like terms. When the terms have two variables, it gets a little bit tricky to figure out which terms are like terms. In this article, we review some examples and give you a chance for you to practice the skill yourself.
Adding and subtracting polynomials is all about combining like terms. The polynomials in this article have two variables, which makes figuring out which terms are like terms a little more difficult.

## Example 1

Simplify.
left parenthesis, minus, 7, d, cubed, minus, 5, d, cubed, f, cubed, minus, 3, f, cubed, right parenthesis, minus, left parenthesis, 8, d, cubed, plus, 4, d, cubed, f, cubed, plus, 2, f, cubed, right parenthesis
Rewrite without parentheses:
start color #11accd, minus, 7, d, cubed, minus, 5, d, cubed, f, cubed, minus, 3, f, cubed, end color #11accd, start color #ca337c, minus, 8, d, cubed, minus, 4, d, cubed, f, cubed, minus, 2, f, cubed, end color #ca337c
Group like terms:
left parenthesis, start color #11accd, minus, 7, d, cubed, end color #11accd, start color #ca337c, minus, 8, d, cubed, end color #ca337c, right parenthesis, plus, left parenthesis, start color #11accd, minus, 5, d, cubed, f, cubed, end color #11accd, start color #ca337c, minus, 4, d, cubed, f, cubed, end color #ca337c, right parenthesis, plus, left parenthesis, start color #11accd, minus, 3, f, cubed, end color #11accd, start color #ca337c, minus, 2, f, cubed, end color #ca337c, right parenthesis
Simplify:
minus, 15, d, cubed, minus, 9, d, cubed, f, cubed, minus, 5, f, cubed

## Example 2

Simplify.
left parenthesis, u, squared, plus, 5, u, squared, v, plus, 4, u, v, squared, right parenthesis, minus, left parenthesis, u, squared, plus, 5, u, squared, v, squared, plus, 4, u, v, right parenthesis
Rewrite without parentheses:
start color #11accd, u, squared, plus, 5, u, squared, v, plus, 4, u, v, squared, end color #11accd, start color #ca337c, minus, u, squared, minus, 5, u, squared, v, squared, minus, 4, u, v, end color #ca337c
Group like terms:
left parenthesis, start color #11accd, u, squared, end color #11accd, start color #ca337c, minus, u, squared, end color #ca337c, right parenthesis, start color #11accd, plus, 5, u, squared, v, plus, 4, u, v, squared, end color #11accd, start color #ca337c, minus, 5, u, squared, v, squared, minus, 4, u, v, end color #ca337c
Simplify:
minus, 5, u, squared, v, squared, plus, 5, u, squared, v, plus, 4, u, v, squared, minus, 4, u, v
Want to see another example? Check out this video.

## Practice

Problem 1
Simplify.
left parenthesis, minus, 2, x, start superscript, 4, end superscript, plus, 7, x, squared, y, minus, 7, right parenthesis, plus, left parenthesis, minus, 9, x, cubed, plus, 7, x, y, plus, 7, right parenthesis

Want more practice? Check out this exercise.