Question

when lenght of a rectangular plot is increased by 4 times its perimeter become 280 metre and area become 12800 what is its original lenght​

Answer 1

Step-by-step explanation:

Let the initial length be x and breadth be y.

Then Perimeter is 2(4x+y)=480

and area is 4x(y)=12800

You can solve these simultaneously and obtain a value for x.

Substitute the value of y from equation 2 to equation 1

i.e 2(4x + 12800/4x) = 480

(x-20)(x-40)=0

x=20 or x=40

There are 2 possible values for the length for this case.