Find the area of a square whose sides are x+1 in sides

The area of a square can be found with the formula s², where s is the side length of the square.

           s²            Plug in the value
       (x + 1)²         Expand
  (x + 1)(x + 1)      Use FOIL (First, Outside, Inside, Last) to multiply
x² + 1x + 1x + 1   Combine like terms (1x and 1x)
   x² + 2x + 1