Answer:

1.  Length = 2w - 3

2.  There are three possible expressions to find the perimeter: 

      expression 1:      w + (2w - 3) + w + (2w - 3) = w + 2w + 2w + w – 3 – 3 = 6w – 6

                                add the sum of the sides of the rectangle                                               

      expression 2:      2w + 2(2w - 3) = 2w + 4w – 6 = 6w - 6                     

                                2 times the width and 2 times the length          

      expression 3:      2(w + 2w - 3) = 2w + 4w – 6 = 6w - 6

                                multiply the sum of the width and length by 2