Answer: 64m ^ 2
Step-by-step explanation:
Let, breadth of rectangle is x, then 5x−4 be the length of the rectangle.
Perimeter of rectangle =2(l+b)
⇒40=2(l+b)
⇒40=2(5x−4+x)
⇒40=12x−8
⇒12x=40+8
⇒12x=48
⇒x=
12
48
⇒x=4
Breadth =4 meters
Hence, length =5×4−4=20−4=16m
Therefore, area of rectangle =lb=16×4=64m ^2
