Question

The area of a small rectangular plot is 84 m^2. If the difference between its length and breadth is 5m;find its perimeter.

Answer 1

length = l
breadth=b
area= lb= 84
(l-b)= 5
(l+b)²-(l+b)²= 4lb
(l+b)²= 4x84+25= 361
l+b= 19
perimitr=2(l+b)= 38

Answer 2

let length be x and breadth be y
xy=84. x-y=5
now (x+y)^2=(x-y)^2+4xy=25+4×84=361
(x+y)= 19
perimeter=2×19 m=38m