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