Is X affine, quasi affine or neither?

Question

Let $X=Q-L$ where $Q$ is quadric defined by $xz=yw$ and $L$ is the line defined by $x=y=0$.

My efforts:

Using Segre embedding I can identify $Q$ as $P^1 \times P^1$. Now how should I proceed?

Edit:

I can identify $Q-L$ with $A^1 \times P^1$.