Answer: Yes, it describes y as a function of x.
Step-by-step explanation:
A function describes y as a function of x if we have:
y = f(x)
where f(x) can be any function.
in this particular case, we have:
y = -x
so we can get this like f(x) = -x, that as we know this is a function of x.
then the relation y = -x is a function of x.
Another way to see it is that this actually is written as:
y = -1*x
the variable that is not being affected is the one being described, (in this case y) and the other variable is the variable of the function (in this case x.)
