Really basic quadratic function problem

[YoungPhysicist]

I can't come up with this function for hours:

I just started to learn quadratic functions so there must be an obvious solution for this which I clearly missed...

 

[mfb]

It has two different values of y for some values of x. It cannot be a function of x. You can find an expression for f such that x=f(y).

 

[YoungPhysicist]

It has two different values of y for some values of x. It cannot be a function of x. You can find an expression for f such that x=f(y).

I am awared of that, the closest thing that I can come up with looks like this:

I have a problem of shifting the entire parabola upwards

 

[YoungPhysicist]

Never mind.Problem solved