All curves on the XOY plane satisfy one condition: the z coordinate is zero. Therefore, if you want to find the curve projection equation of this curve on the XOY plane, you only need to make Z=0.

The projection equation of this curve on the XOY plane is:

X^2+Y^2=9,X= 1

X= 1，Y=2√2。

So the projection of this curve on the XOY plane is actually a point with coordinates (1, 2√2).