A mathematical operation of subtracting an algebraic term from its unlike algebraic term is called the subtraction of unlike algebraic terms.
The unlike algebraic terms appear in subtraction form to represent the subtraction of an algebraic term from its unlike algebraic term. Actually, the unlike algebraic terms have different literal factors. Due to this reason, an algebraic term is unable to subtract from its unlike term but the subtraction of them can be represented by an expression.
$6xy$ and $4x^2$ are two unlike algebraic terms.
Assume, the term $6xy$ is subtracted from another algebraic term $4x^2$. First write the term $4x^2$ and then $6xy$ but a place a negative sign to represent subtraction of them.
The literal factor of the term $4x^2$ is $x^2$ and the literal factor of $6xy$ is $xy$. They both are different literal factors. Hence, it is not possible to perform subtraction but the subtraction of them is written in the form an expression.
Observe the following examples to know how to represent subtraction of unlike algebraic terms in mathematical form.