Login

The area of Rectangular plot is 96m2. If the perimeter is 40 m. Find the length and breath of the plot.(use hit and trail method)

Let 'l' be the length and 'b' be the breadth of the rectangular plot.
According to the question,
Perimeter = 40


Area = 96

We have to find 2 numbers such that their product is 96 and sum is 20. These 2 numbers will be 12 and 8.
Therefore length of rectangular plot is 12cm and breadth is 8cm. 

  • -1
View Full Answer

Given:

perimeter =2(l + b) = 40m

area = l x b = 96 sq.mtr

Solution: 

Perimeter = 2(l + b)=40

                 l + b = 40/2 = 20

                  l = 20-b   .........(1)

Area = l x b =96

App (1), area = (20-b)x b=96

       20b-b^2 = 96

        -b^2 + 20b -96 = 0

         b^2 -20b+96 =0

 b^2 - 12b -8b +96 = 0Applying qdr. formula

b(b-12) -8(b-12) = 0

(b-12) (b-8) =0

b=8 or 12

If b=8, then l = 12

If b=12, then l=8.

  • 4
What are you looking for?