Draw a cylinder in the 3D coordinate plane with a radius of 3 units, a height of 7 units, and a center at (3, 3, 0).
First, we need to figure out where our base is. A circular base with a center at (3, 3, 0) would look like this on the x-y plane.
Extended 7 units down the z-axis, the cylinder would look like this.
Hopefully your drawing looks more or less like that.