Like terms have exactly the same variables raised to exactly the same powers. 3x and 7x are like terms and combine to 10x; 3x and 3x squared are not, and cannot be combined at all.
Math Dictionary / Like Terms
Like Terms
Like terms have the same variable parts raised to the same powers.
AlgebraGrade 6Grade 7Grade 8Algebra 1GEDSATACT
What it means
Only like terms can be combined by adding or subtracting their coefficients.
Also called: similar terms
Examples
| 3x and 8x are like terms |
| 5a^2 and -2a^2 are like terms |
| 4x and 4y are not like terms |
Common mistake
Terms must have the same variables and exponents to be like terms.
Try one
Question: Can 7x and 2x be combined?
Show answer
Yes. They are like terms.