Let the width be x
Width = x
Length = 2x - 3
Perimeter = 2 ( Length + Width) = 2 ( x+ 2x - 3) = 2(3x - 3) = 6x - 6
Given that the Perimeter is 42 feet,
6x - 6 = 42
6x = 42 + 6
6x = 48
x = 8
Width = x = 8 feet
Length = 2x -3 = 2(8) - 3 = 13 feet
Answer: The length is 13 feet.