3 ms·

Isn't that possible considering planes in more than two dimensions?

• gjm11 17y ago
  Not unless either Twitter or email equals zero. (Unless you take "orthogonal" and "parallel" to mean "there's a vector in one and a vector in the other that are orthogonal/parallel".)
  • DrJokepu 17y ago
    If I remember correctly, two lines being both parallel and orthogonal is quite possible in Hyperbolic (Non-Euclidean) Geometry.
    • 10ren 17y ago
      Parallel lines of longitude converge orthogonally at poles.