Answer
Hyperboloid of two sheets.
See image:
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Work Step by Step
The equation has the form of a Hyperboloid of two sheets. as found in Table 11.1, with variables y and z interchanged.
The hyperboloid opens along the y-axis. Cross-sections with planes $y=k$ are ellipses. Cross-sections with planes parallel to $x=0, z=0$, are hyperbolas.
