Question 636441
let the length of the rectangle be l
and breadth be b
ATQ 2(l+b)=30
so l+b=15...........eq^n 1
lb=54.............eq^n 2 
so l-b=sqrt{(l+b)^2-4lb}=sqrt{15^2-4*54}=sqrt(225-216)=sqrt 9=3........eq^n 3
adding eq^n 1 & 2 
    2l=18
    l=18/2=9
    b=15-9=6  ans