yes.
They are identical or equivalent.
Expressions have to contain numbers and letters.
Like terms.
Yes. It is equal to zero. Yes, mathematical expressions can contain numbers, variables, and mathematical operations but do not contain an equal sign or inequality sign.
yes.
Two expressions are "equivalent" if they have the same result for any values of the variable or variables.
Terms that contain the same variable is called "like terms".
There is no specific name. They can be fractions which contain algebraic or trigonometric or non-integral exponential expressions.
They are identical or equivalent.
Expressions have to contain numbers and letters.
Like terms.
In the same way that you would factorise any other expressions that do not contain an equality sign depending on the expressions of which none have been given.
Terms that contain the same variable is called "like terms".
Algebraic expressions may contain variables but they are not normally called variables. In fact, if they are related to identities, they need not be variable. For example, (4x2 + 8xy + 4y2)/(x + y)2 is an algebraic expression, but it is not a variable: it equals 4.
Yes. It is equal to zero. Yes, mathematical expressions can contain numbers, variables, and mathematical operations but do not contain an equal sign or inequality sign.
The same as in many other expressions. It is a variable, that is, it can be replaced by any number.