Question

The length of a rectangular hall is $5m$ more than its breadth. The area of the ball is $750m^2$. Find the perimeter of the hall

Answer 1

Let the length of the rectangular hall $=l$ m and breadth $=b$ m.
Given, $l=b+5$
Area of the rectangle $=l\times b=750m^2$
$(b+5)\times b=750$
$b^2+5b-750=0$
$b^2+30b-25b-750=0$
$(b-25)(b+30)=0$
$=>b=25$ or $-30$
As breadth of the rectangular hall cannot be negative, breadth $=25m$
Now, length $l=25+5=30m$
Perimeter of the rectangular hall $=2(l+b)=2(30+25)=110m$