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.
That way your drain portion is within the heated space but the vent is in the exterior wall. Once your vent is above the fixture level such as in your attic you can run it horizontally over to another vent so you only put one hole through the roof. The make sure the vent has a slight slope to drain so it doesn't funstion as a trap for condensation.