Answer
The expression represented the perimeter of a rectangle be 12x -8 units .
Reason
Formula
Perimeter of rectangle = 2× (length + breadth)
As shown in the diagram
Length = (3x-1) units
Breadth = (3x-3) units
Put this in the formula
Perimeter of rectangle = 2 × (3x - 1 + 3x - 3)
= 2× (6x - 4)
= 12x -8 units
Hence Proved
