Answer:
Perimeter of the rectangle=6x+8 square units
Explanation:
Given that area of rectangle is

Area of rectangle=lw square units




Comparing the above equation with the given area we get
lw=(x+3)(2x+1)
Therefore length=x+3 and width=2x+1
To find the perimeter :
Perimeter of the rectangle=2(l+w) square units




Therefore perimeter of the rectangle=6x+8 square units