Question

. Find the perimeter of a rectangular field whose length is four times its width and which has an area equal to 30976 cm2.

Answer 1

breadth= x
∴length= 4x
area= l x b
but area = 30976
∴30976= (4x) (x)
= 30976= 4x²
 x²= 30976/4
x²= 7744
x= √(7744)
x= 88
∴breadth= x= 88
length= 4x= 4x88= 352
perimeter= 2(l+b)
          = 2 (352+88)
          = 880
        

Answer 2

according to thegiven data
length(l)=4×width(w)
area of rectangle = 30976
              4w×w=30976
                  w²=30976/4
                     w=√7744
                       w=88
              l=4×88
                l=352
perimeter=2(l+b)
              =2(352+88)
perimeter=2×440
perimeter=880cm