GridWits
Easy tier Technique 7 of 31 Used by Smart Hint

Hidden Pair

Two digits confined to the same two cells in a house clear those cells of everything else.

How it works

  1. 1Find two digits in a house that between them can only go in the same two cells.
  2. 2Those two cells must take those two digits, in one order or the other.
  3. 3Every other candidate in those two cells is therefore impossible — strike them.
Next in the ladder Pointing Pair/Triple →

A digit confined to one row or column within a box is eliminated from the rest of that line.