Most visitors to this site keep a pretty close watch on their system. When a new user account suddenly appears on the system it's no surprise it's a matter of concern and raises more than a few questions. It turns out UpdatusUser is part of the NVIDIA driver package for their graphics cards.
Coplanar Lines. Coplanar Lines are lines which lie on the same plane. Two parallel lines or two intersecting lines always lie in a plane. Thus, two line are coplanar, if and only if they are either parallel or intersecting. Lines in three dimensional space are coplanar, only if they are not skewed lines. Two lines which are neither parallel nor intersecting are called skewed lines.
Theorem 2: If two coplanar lines are perpendicular to a third line, then they are parallel to each other: This is a special case of the more general result that when two coplanar lines are cut by a transversal and corresponding angles are equal, then the lines are parallel.