Is x equals -2 a function?

Answer 1

If you are speaking of an entity which has a graph on the xy plane that is of the form

y = f(x)

then it IS NOT a function.

An equation which defines a relation on the xy plane is the equation of a

function, if and only if it has a graph that is not crossed more than once by

a vertical line. However the graph of x=2 is indeed a vertical line in the xy

plane consequently IT IS NOT A FUNCTION.

In most algebra and precalculus courses, the concept of function is assumed

to refer to a function y=f(x). However if we were to think in the reverse direction

where y was an independent variable and x were the dependent variable, then

we could assert that it is a function x=f(y) = 2 which is now a constant.

For most basic courses in mathematics however, your answer is NO, it is not a function.

Answer 2

No, that is just an X co-ordinate.

A function must either be given in terms of f(x) or y.