Parabolas can be the only conic sections that are considered functions because they pass the vertical line test. We have worked with parabolas before in quadratic equations, but parabolas formed by conic sections are a little different.
Toilet drainage rough-in steps. 1  Cut a hole in the subfloor just large enough for the bottom part of the toilet flange to sit. 2  If your installing the drainage underground, excavate the trench and have a supply of clean backfill ready (sand or gravel) to grade and cover the pipe.
Without a vent pipe, flushing your toilet would be like trying to get all the water out of a straw with your finger held tightly to the top of the straw. It is frustrating to have leaks around the vent stacks BUT the leaking in your ceiling are not caused by rainwater flowing thru the stack vent pipe itself.