The use of the letter x as a mathematical unknown is a relatively modern convention. Algebra has been around for a lot longer. Daryl Benson/Stockbyte via Getty Images You might be most familiar with x ...

It is the perfect movie mystery plot. A problem unsolved for decades. A hero drawn into the search for a solution many think does not exist. The hero gives up, only to be drawn back in. After years of ...

Blue Prince follows in the storied tradition of mystery house games while mixing in logic riddles, word games, math problems and many codes and passwords. By Rollo Romig The mystery house, in which ...