# "Like Terms"

## Like Terms

"Like terms" are terms whose variables (and their exponents such as the 2 in x2) are the same.

In other words, terms that are "like" each other.

Note: the coefficients (the numbers you multiply by, such as "5" in 5x) can be different.

### Example:

 7x x -2x

Are all like terms because the variables are all x

### Example:

 (1/3)xy2 -2xy2 6xy2 xy2/2

Are all like terms because the variables are all xy2

## Unlike Terms

If they are not like terms, they are called "Unlike Terms":

Unlike Terms Why they are "Unlike Terms"
-3xy -3y 12y2 these are all unlike terms
(xy, y and y2 are all different)

### Example: These are all Unlike Terms because the variables and/or their exponents are different:

 2x 2x2 2y 2xy

## Combining Like Terms

You can add like terms together to make one term:

### Example: 7x + x

They are both like terms, so you can just add them:

7x + x = 8x

### By the way ... why don't we write "1x" ?

It is just easier to write x. Imagine adding eggs:

7 eggs plus 1 egg is 8 eggs is written 7 eggs + egg = 8 eggs

### Example: 3x2 - 7 + 4x3 - x2 + 2

Some of the terms are like terms.

Combine like terms:

(3x2 - x2) + (4x3) + (2 - 7)