Question

what is the x intercept of f(x) x^2+2

Answer 1

the vertex = (0,2)

Answer 2

you mean
f(x)=x^2+2
your y intercept is (0,2)
now sub f(x)=0 and solve for x
0=x^2+2
that will be your x-intercept

Answer 3

but you can';t because the x is a negative

Answer 4

https://www.desmos.com/calculator
Use this to graph your functions.
It is possible not to have an x intercept.
Notice the graph does not cross the x axis at all, that means that you do not have an x intercept.