Length of the side of the original Square

Question

It's the size of a square or decreased by 2 inches, the area is decreased by 36 in.² what was the length of a side of the original square?

Answer 1

Hi Joanna,

 

Let x represent the length of the original square and x-2 represent the length of a side of the reduced square. Therefore the area of the original square is x² and the area of the reduced square is (x-2)². Since the area was decreased by 36 in.², then 

                       

                        x² - (x-2)² = 36

                      x² - (x² - 4x +4) = 36

                      x² - x² +4x - 4  =  36

                                  4x - 4  =  36

                                         4x = 40

                                           x = 10  Therefore, the length of the original square is 10 in.