It is an algebraic term.
an equation
An expression.
An expression.
it using the word x and y
it is a varible
Numerical Expression
Expression
It is an expression.
It is an expression.
Expression
It is an algebraic expression.
The answer will depend on what you mean by symbols. I suggest that it is neither an equation, expression nor formula - just a collection of symbols. If you have some numbers, operators and variables then it may be a formula, but even then, only if the collection is in a proper order. For example, 3*/4+(4/0)-/7.59 is a nonsense collection of symbols and numbers.