Answer
The path would have been a half-circle.
Work Step by Step
According to the Review & Summary on page 827: "A charged particle with mass $m$ and charge magnitude $\vert q \vert$ moving with velocity $v$ perpendicular to a uniform magnetic field will travel in a circle."
Since the particle enters the magnetic field moving directly to the left, the particle will travel through a half-circle and leave the magnetic field moving directly to the right.
The path would have been a half-circle.
