how do you solve xy=1 and is it a function

Question

the question asks for solving and if its a function or not

Answer 1

Just substitute any x-value in.
For example, put in x = 5.
You will get:

(5)y = 1
y = 1/5

Thus, (5, 1/5) is a solution.
This shows that there are infinitely many solutions, and you just to plug in a random x-value to get a corresponding y-value to have a set of solution.

And yes, this is a function.
Rearranging, you will get y = 1 / x, which is a rational function.