# 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":

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

2x
2x2
2y
2xy

because x, x2, y and xy are all different

### Example: these are also unlike terms

−3xy
−3y
12y2

because xy, y and y2 are all different

## 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 simpler to write x, and is so common that "1x" looks strange.

### Example: 4x3 + 3x2 − 7 − x2 + 2

Some of the terms are like terms.

Combine like terms:

(4x3) + (3x2x2) + (2 − 7)