# Introduction of Algebraic Expressions

A mathematical expression that contains a variable is called an algebraic expression.*x*

^{2}, 3

*x*â€“ 2

*y*, . Two algebraic expressions are called like terms if both the variable parts and the exponents are identical. That is, the only parts of the expressions that can differ are the coefficients.

*y*

^{3}and are like terms, as are

*x*+

*y*

^{2}and â€“7(

*x*+

*y*

^{2}). However,

*x*

^{3}and

*y*

^{3}are not like terms, nor are

*x*â€“

*y*and 2 â€“

*y*.